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Archive for the ‘CRISPR’ Category

Following a fungus from genes to tree disease: a journey in science

Published: June 30, 2022 9.36am EDT

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  1. Brenda WingfieldPrevious Vice President of the Academy of Science of South Africa and DSI-NRF SARChI chair in Fungal Genomics, Professor in Genetics, University of Pretoria, University of Pretoria

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Brenda Wingfield receives funding from the South African Department of Science and Innovation via the National Research Foundation (NRF). She is a fellow of the Academy of Science of South Africa, African Academy of Science and the Third World Academy of Science She is the Secretary General of the International Society of Plant Pathology and a fellow of the American Phytopathological Society She is the current chair of the NRF Executive Evaluation Committee

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Anyone who reads even a little about science and technology will be familiar by now with the idea of genome sequencing. This process involves breaking an organism’s DNA into fragments to study their compositions or sequences. Then the fragments are aligned and merged to reconstruct the original sequence.

But why sequence an organism’s genome? What’s the value for ordinary people and the world more broadly? The answers are immediately obvious when it comes to the medical field. Understanding what makes a disease “tick” offers scientists a way to treat or prevent it. Sequencing the genome of a crop or animal can improve agricultural yields or make species hardier in shifting climates.

It’s a little tougher to explain the value of sequencing the genome of plant pathogens, the organisms that cause diseases in plants. But this has become a critical part of the work of microbiologists and plant pathologists. And it is important, far beyond the laboratory: by carefully studying plant pathogens’ genomes, researchers have been able to design specific double stranded RNA fungicides to short circuit some pathogens’ abilities to harm plants.

These fungicides have not yet been deployed commercially but have huge potential – only targeted species will be affected and so the process is likely to be more environmentally friendly than any involving chemical fungicides. This research has the potential to protect crops, benefiting agriculture and contributing to food security.

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For the past 13 years I’ve focused on sequencing one plant pathogen’s genome. Here’s where that scientific journey has led.

Pine trees at risk

sequenced the genome of a fungus called Fusarium circinatum in 2009; it was the first fungal genome sequence to be conducted on the African continent.

I started studying this pathogen more than 20 years ago because it was killing seedlings in South African pine nurseries. Fusarium circinatum causes pitch canker on pine trees, which makes trees exude pitch or resin. In severe cases the fungus causes tree death. This fungus is considered to be the most important pathogen threat to the global plantation pine industry. It is also potentially devastating in some areas of the southern US, Central America, Europe and Asia, where pines are found naturally.

Trees are extremely important in carbon sequestration. They also produce oxygen – it is estimated that, daily, one tree can produce enough oxygen for four people. Trees have huge economic value, too, providing timber for our homes and paper and packaging for many uses in our daily lives. It is difficult to estimate the total value of pine plantations globally but the South African industry is estimated to contribute more than US$2 billion to the country’s Gross Domestic Product annually.

Sequencing the genome was just the beginning. Follow-up studies published in 2021 involved knocking genes out of the genome and studying what happened. This process is a bit like first identifying and lining up all the parts, then removing these parts one at a time to see what difference they make to the functioning of the fungus. Sometimes we need to understand how gene products (proteins) interact with each other and then more than one gene might be removed from a genome.

In this way, my colleagues and I can learn which genes are important to the processes that Fusarium circinatum uses to cause pitch canker and which are not. Now we’re working to target the important genes in studies to manage the pathogen.

It’s time-consuming work: this fungus has around 14,000 genes. This is more than the yeast that is used to ferment beer, which has 6000 genes, but less than the estimated 25,000 genes in the human genome. Luckily technologies are evolving rapidly to enable routine gene knock-outs. This involves a protein which acts a bit like DNA-specific scissors allowing deletion of a specific sequence of DNA. The position where the protein cuts is guided by using small pieces of RNA sequence that are identical to the target DNA sequence.


Read more: What is CRISPR, the gene editing technology that won the Chemistry Nobel prize?


Another of our key findings is that Fusarium circinatum has acquired, through horizontal gene transfer from other organisms, a group of five genes that apparently enhance its growth.

This discovery has been very useful in developing a specific diagnostic tool using LAMP PCR (Loop-mediated isothermal amplification) to identify this pathogen. This is a special kind of highly sensitive test that was developed to allow for in-field detection of pathogens. It also doesn’t require specialised training. This is useful because trees only recently infected with Fusarium circinatum can be asymptomatic. It’s crucial to determine the presence of the pathogen as early as possible so its spread can be better managed.

New skills, new possibilities

The rise in studies that sequence plant pathogens’ genomes has also opened up opportunities for scientists to develop new skills. The data generated by genome sequencing sometimes outstrips the number of researchers available to analyse it. During pandemic lockdowns in South Africa, some students in my research programme learned how to code and developed skills in bioinformatics, using computers to capture and analyse biological data rather than working in a laboratory.

With these new skills, as well as fast-improving technology, we may well crack Fusarium circinatum’s code once and for all. And that will help to guard pine trees against a dangerous, costly pathogen.

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What role can genetics play in ‘designing’ more sustainable crops, livestock and trees?

Rodolphe Barrangou | National Academy of Engineering | July 1, 2022

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Plants, animals and microbes can be improved with gene editing. Credit: Carys-ink
Plants, animals and microbes can be improved with gene editing. Credit: Carys-ink

The ability to engineer genomes and tinker with DNA sequences with unprecedented ease, speed, and scale is inspiring breeders of all biological entities. Genome engineers have deployed CRISPR tools in species from viruses and bacteria to plants and trees (whose genome can be 10 times larger than the human genome), including species used in food and agriculture (Zhu et al. 2020).

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Starting small, bacteria used in food fermentations have had their genomes enhanced to optimize their functional attributes linked to the flavor and texture of fermented dairy products such as yogurt and cheese. The fact that CRISPR-Cas systems provide adaptive immunity against viruses in dairy bacteria led to the commercial launch, more than a decade ago, of bacterial starter cultures with enhanced phage immunity in industrial settings. Most fermented dairy products are now manufactured using CRISPR-enhanced starter cultures. Since then, a variety of bacteria, yeast, and fungi (figure 2) involved in the manufacturing of bioproducts has also been CRISPR enhanced to yield commercial products such as enzymes, detergents, and dietary supplements.

Moving along the farm-to-fork spectrum, most commercial crops—from corn, soy, wheat, and rice to fruits and vegetables—have had their genomes altered (figure 2). Genome engineering is used to increase yield (e.g., meristem size, grain weight) and improve quality (e.g., starch and gluten content), pest resistance (e.g., to bacteria, fungi, viruses), and environmental resilience (e.g., to drought, heat, frost). For instance, nonbrowning mushrooms with extended shelf life can be generated, and tomatoes with increased amounts of gamma aminobutyric acid (GABA) to enhance brain health have been commercialized. In addition, efforts are underway to enhance nutritional value.

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Credit: NAE

Livestock breeders have joined the fray, with genome engineering of main farm species such as swine (leaner bacon), poultry (CRISPR chicken), and cattle (for both meat and dairy). Swine have also been edited with a viral receptor knockout to prevent porcine reproductive and respiratory syndrome; the approach is being evaluated for regulatory approval (Burkard et al. 2017). Breeding applications include hornless cows (for more humane treatment), resistance to infectious disease (tuberculosis in cattle), and removal of viral sequences in the genome of elite commercial livestock,[1] notably swine. The CRISPR zoo also encompasses genetically diverse species—fish (tiger-puffer and red sea bream), cats (efforts are underway to develop hypoallergenic variants), and even butterflies (wing pattern)—illustrating the ability to deploy this technology broadly.

This is an excerpt. Read the original post here

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Kenyan gene hacker moves to defeat witchweed

Prof Steven Runo has edited the DNA of sorghum to give it resistance to the notorious, parasitic weed

In Summary

•Traditionally, farmers would attempt to control Striga by simple, physical means. These included physically uprooting the plants, which wasn’t particularly effective, considering that the weed knots itself within the host’s roots.

•Prof Runo is an associate professor of molecular biology at Kenyatta University.

Among the towering names in genome editing in Kenya is Professor Steven Runo

The world is making tremendous strides in the novel science of genome editing, which has wide-ranging applications in medicine and agriculture, among other fields.

Kenyan scientists have also joined the effort, with several pioneering research projects underway right within the country.

Among the towering names in genome editing in Kenya is Prof Steven Runo, an associate professor of molecular biology at Kenyatta University. Part of his research work targets Striga, also known as witchweed, a notorious weed that threatens maize, sorghum, rice and several other cereal crops.

Known in parts of western Kenya, where it is particularly rife, as Uyongo or Kayongo, Striga is a predatory plant that attaches itself to the roots of the host plant, from where it saps vital nutrients from the host. This invariably leads to stunted growth and vastly diminished production.

“Genome editing is a new technology for not only plant breeding but also animal breeding,” Prof Runo said.

“It’s a very simple strategy. Think about the DNA, which is what determines the traits of organisms. How tall or short we are, and how much yield you get from a crop, is determined by the genetic code”.

With this in mind, scientists like Prof Runo are able to introduce changes to an organism’s DNA, with an aim to alter specific traits in the organism.

“Genome editing involves going into the genome and introducing beneficial changes, and very precisely at that,” he said. “So, you can go into a specific trait and alter one or two bases – or DNA sequences – to achieve the trait that you are looking for. One of the ways that genome editing can be done is using CRISPR Cas9 technology, a very simple alteration of DNA sequence for beneficial traits”.

Traditionally, farmers would attempt to control Striga by simple, physical means. These included physically uprooting the plants, which wasn’t particularly effective, considering that the weed knots itself within the host’s roots.

And upon maturity, the weed deposits its seeds in the soil, which makes it difficult for farmers to control it.

Farmers would also practice crop rotation or intercropping with legumes, which helps control Striga’s germination. They would also apply inorganic fertiliser to enrich the soils, as Striga thrives in poor soils within low-rainfall regions.

The use of pesticides would also be recommended as a control measure against Striga, but chemical controls are normally not within reach of many small-scale farmers.

“While a few control measures have been moderately successful, the problem still persists, especially in western Kenya, eastern Uganda and lake zone of Tanzania, where farmers have frequently voiced their frustrations at the ubiquity of this invasive weed,” states The International Maize and Wheat Improvement Center (CIMMYT).

That’s where biotechnology chips in, with novel technologies that aim at controlling the proliferation of pathogenic plants, and minimizing the labour and costs in pesticides that farmers would ordinarily incur.

Prof Runo’s project, titled “Evaluation of Striga resistance in Low Germination Stimulant 1 (LGS1) mutant sorghum”, seeks to confer resistance to this parasitic weed in sorghum, an important cereal crop in Kenya and many parts of Africa.

A proof of concept has already been done for the project, and the program awaits other stages in product development, which will ultimately culminate in trials.

“This weed is present in most parts of Sub-Saharan Africa, and Kenya is one of those countries that is heavily infested by the parasite,” Professor Runo told Tuko recently.

“Depending on the level of infestation, Striga can cause between 30-100 percent in yield losses. We estimate this to cost about US$ 7 billion globally every year. This is a substantial amount of money, considering that this weed affects cereal crops, mostly grown by small-scale farmers”.

Many counties in Western Kenya have Striga infection, he adds – from Busia to Siaya, Kisumu and Homabay.

“Almost all countries within western Kenya have Striga infection”.

He is honored to be at the forefront of such groundbreaking research, and appreciates the opportunity to deploy his expertise in this highly complex science towards finding solutions for common problems that have dogged local farmers.

“You’d be happy to know that Kenya has very good human resource in terms of very well trained scientists. What we want to showcase is that these scientists can do research that is comparable to research that is done in other countries. Again, we have a long-standing history of using advances in plant sciences to develop and grow better crops”.

There are plenty of good reasons to support local scientific expertise, he adds, citing the case of Asia.

“The success that we are seeing in Asia, in terms of agricultural advancement, was because scientists were supported. They’d say, we have a critical number of scientists that have innovations, and they’d use science-based and evidence-based facts to support and make decisions and policy in agriculture. Such an approach goes a long way towards growth improvement, and ultimately improves food security”.

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How is Rwanda faring in agricultural bio-technology?

Michel NkurunzizaBy 

Michel NkurunzizaPublished : June 28, 2022 | Updated : June 29, 2022

Agricultural experts are making a case for adopting agricultural biotechnology as crop production remains insufficient for both local consumption and exportation yet Rwanda’s economy relies on agriculture.

Plant or agricultural biotechnology bio-technology can be defined as the use of tissue culture and genetic engineering techniques to produce genetically modified plants that exhibit new or improved desirable characteristics.

Bio-technology has helped to make both insect pest control and weed management safer and easier while safeguarding crops against devastating diseases.

According to the recent publication “Plant biotechnology: A key tool to improve crop production in Rwanda” published in African Journal of Biotechnology by  Leonce Dusengemungu, Clement Igiraneza and Sonia Uwimbabazi, intensive and appealing discussions about agriculture economic importance, production of improved crops and the use of all necessary resources to ameliorate agricultural production need more attention.

Agricultural experts are making a case for adopting agricultural biotechnology as crop production remains insufficient for both local consumption and exportation yet Rwanda’s economy relies on agriculture. Photo: Sam Ngendahimana.

The study aimed at gathering the information on Rwanda’s agriculture based on different research reports and Rwandan’s government established policies to identify constraints to agricultural production faced by farmers and applicability of plant biotechnology.

“Rwanda as any other Sub-Saharan African countries are in need of free-disease plantlets for highly cultivated crops and to achieve this, plant biotechnology holds the key to high agricultural productivity.

Use of plant biotechnology has to be highly considered as a means to solve some agri-related problems since its benefits can speed up the economy and stimulate the research processes,” they said.

According to the researchers, Rwanda’s farming suffers shortage of quality planting materials due to few production companies or organizations of good quality seeds.

“It is desirable for farmers to use quality seeds that are of high value that can benefit them. That is why more proper seed storage units, tissue culture production units and other possible alternative methods to increase the number of quality planting materials are needed,” they said.

The trio said that the use of biotechnology tools to protect seed distributed among farmers, biological control agents and testing varieties of seed identity and purity before their distribution are primary tools that can benefit African farmers.

“In this context, it is recommended for developing African countries to start thinking about pursuing gene transfer to breed-disease and introduction of pest resistant varieties in order to meet the future food’s needs,” they recommended.

The modern agriculture biotechnology, they said, is needed as the conventional agricultural research does not keep an equal distribution between the high demand of food and the supply chain.

Despite the difficulties in sharing information between scientists across the country, they said, the information gathered about the current status of plant biotechnology in Rwanda from some researchers in Rwanda Agriculture Board (RAB) have reported the use of tissue culture: in vitro cultivation of cash crops like banana, coffee, potato, sweet potato, pineapple, passion fruit, Tamarillo also known as a tree tomato.

“Several private companies have also initiated in vitro production of crops including bananas. The effort made still does not provide enough for the high demand of plantlets from the farmers. Disseminating resistant varieties produced using plant breeding technology is highly recommended since most of the varieties that are brought from abroad sometimes fail to adapt,” the trio suggested.

They suggest more research is needed to identify and use suitable domestic breeding techniques for popular varieties in the country, and this should be widespread to other crops since the only crops receiving research attention are common beans, bananas, cassava and sweet potatoes.

Plant biotechnology status in Rwanda

Rwanda’s plant biotechnology is mostly dominated by tissue culture of medicinal plants and micro-propagation of disease-free food crops mainly bananas, potato, sweet potato and cassava.

“To ensure food security, appropriate measures to increase the capacity of plant biotechnology should be a priority,” they said.

Tissue culture practiced in Rwanda is one of the techniques that is believed can solve agriculture production problems because it has so many advantages, one of them being the high multiplication of plantlets in a short time and space.

The plants produced with tissue culture techniques are also known to be free of viruses and other diseases; thus, are all with high survival rate in the field.

In Rwanda, University of Rwanda (UR), Rwanda Agriculture Board (RAB), INES-Ruhengeri, FAIM.CO are all among the few organizations that have undertaken the biotechnology programme, and it has been a few years now, but the impact of that program on Rwandan people’s livelihood is still debatable.

“Further, it is mainly because the research that is conducted does not initiate the production of affordable products that can reduce the need of costly agrochemicals and deleterious effects of diseases and weeds thus promoting agricultural productivity,” they said.

Considering the potential benefit that plant biotechnology holds, it should be considered in the framework of the agricultural sector at large perceiving scientific, technical, regulatory, socio-economic and political evolution, they recommended.

It will be very wise to allocate necessary funds for experimentation and research of applicability of modern biotechnology programs: tissue culture, genetic engineering, use of GM crops, use of plant molecular markers especially in developing countries since the demand to apply that technology will always be high, and the future of agriculture will definitely depend on modern plant biotechnology, the study further says.

Janvier Karangwa, the Marketing and Communication Specialist at Rwanda Agriculture and Animal Resources Development Board told Doing Business that , “  in Rwanda, biotechnology is used in breeding, rapid cleaning plant material multiplication via tissue culture technology, diseases diagnosis and surveillance management.”

Will GMOs be adopted in Rwanda?

The reason why farmers in most developed countries have adopted the use of GM crops is because they have seen a very positive income.

According to researchers adopting GM crops will come with a lot of tangible benefits cutting down the number of herbicides, fungicides and other chemicals to control pests.

However, Juliet Kabera, the Director General of Rwanda Environment Management Authority (REMA) recently said that the institution is closely working with Rwanda Agriculture and Animal Resources Development Board (RAB) to ensure that any biotechnology that is used is safe.

“We are the authority to handle biotechnology after Rwanda ratified Cartagena protocol to ensure bio-safety,” she said.

She said that Rwanda has designed a bio-safety strategy to ensure Rwandans are conscious.

“In the strategy we now have a draft of law on biosafety which is going to be discussed in the cabinet and later on in the parliament. We are establishing laboratories and raising awareness to be able to know what we are doing on the market especially when it comes to Genetically Modified Organisms (GMOs),” she said.

According to RAB, to fight Potato late blight disease, a new variety of Irish potatoes, produced through biotechnology, which will not require using agro-chemicals could soon be imported and tried in Rwanda.

According to researchers, in order to revolutionise the plant biotechnology industry in Rwanda and Africa as a whole, initiatives to build strong long-term policies to promote this technology starting by training individuals and increasing the scientific capacities and infrastructures that specialise in plant biotechnology should be recommended.

“Rwandan government should reinforce its current agricultural policies: documenting the available plant breeds by increasing the number of community gene bank and installing proper research units in the whole country, renovating and improving the current plant breeding techniques and training the new generation of plant breeders, limiting the use of agrochemicals to protect the environment,” they suggest.

Open Forum on Agricultural Biotechnology (OFAB) was recently launched in Rwanda with the aim of promoting biotechnology.

OFAB, a project of African Agricultural Technology Foundation (AATF), is funded by the Bill and Melinda Gates Foundation.

According to officials, the experiences and practices in the field of biotechnology will be shared in the countries of Kenya, Uganda, Tanzania, Ethiopia, Ghana, Burkina Faso, Rwanda and Nigeria.

OFAB is a partnership platform in Africa that contributes to creation of an enabling environment for biotechnology research, development, and deployment for the benefit of smallholder farmers in Africa.

It aims to contribute to informing policy decision making processes on matters of agricultural biotechnology through the provision of factual, well researched and scientific information.

editor@newtimesrwanda.com

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17 May 2022/

Ellen Phiddian

Gene-editing cockroaches with CRISPR-Cas9 – and maybe other insects

New technique a lab time-saver for world of insect experimentation.

cartoon of syringe injected into big cockroach, with arrow pointing to three baby cockroaches, one of which has white eyes

The new genetic modification method involves directly injecting CRISPR materials into cockroaches, with some of their offspring then carrying the mutation (in this case, a change in eye pigment). Credit: Shirai et al., Cell Reports Methods

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GENETIC MODIFICATION

Researchers have found a simpler way to genetically modify cockroaches with CRISPR-Cas9, considerably reducing the time needed to conduct insect research.

CRISPR-Cas9 is a molecule first discovered in bacteria, which has made genetic modification a much faster and more efficient process.

The new technique, called direct parental CRISPR, or DIPA-CRISPR, allows researchers to avoid having to microinject CRISPR materials into insect embryos. Apparently, this is a major inconvenience in the genetically modified insect world, and it doesn’t work for every insect. In fact, cockroaches’ odd reproductive systems prevent them from being genetically modified with embryo microinjections.

Instead, DIPA-CRISPR works by a female cockroach being injected with the relevant CRISPR tools – meaning that some of her offspring carry the induced genetic modifications.

“In a sense, insect researchers have been freed from the annoyance of egg injections,” says Takaaki Daimon, a researcher at Kyoto University, Japan, and senior author of a paper describing the research, which has been published in Cell Reports Methods.

“We can now edit insect genomes more freely and at will. In principle, this method should work for more than 90% of insect species.”

The researchers used commercially available Cas9 ribonucleoproteins (the proteins that induce genetic modification) to test this method.

They injected these ribonucleoproteins into the haemocoels (main body cavity) of two different insects: the German cockroach (Blattella germanica), and the red flour beetle (Tribolium castaneum).

They then investigated the offspring of these insects, to see whether their genetic modification had worked.

The Cas9 proteins that were designed to “knockout” genes (that is, remove a gene from a genome) were very successful, by genetic modification standards. More than 50% of the red flour beetle offspring, and 22% of the cockroach offspring, lacked the pigment-creating gene that the researchers wanted to remove.

“Knockin” modifications (introducing a new gene into the genome) were less successful, with only very low efficiency.


Read more: Resilience is in the genes for cockroach


The technique depends on the reproductive stage the adult females are at, and a strong understanding of the insect’s ovary development. Unfortunately, fruit flies – which are a model organism for lots of genetic research – won’t respond to this technique.

Nevertheless, the researchers say that DIPA-CRISPR will reduce the expense, and timeframes, of a lot of insect research.

“By improving the DIPA-CRISPR method and making it even more efficient and versatile, we may be able to enable genome editing in almost all of the more than 1.5 million species of insects, opening up a future in which we can fully utilise the amazing biological functions of insects,” says Daimon.

“In principle, it may be also possible that other arthropods could be genome edited using a similar approach. These include agricultural and medical pests such as mites and ticks, and important fishery resources such as shrimp and crabs.”


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Originally published by Cosmos as Gene-editing cockroaches with CRISPR-Cas9 – and maybe other insectsEllen PhiddianEllen Phiddian is a science journalist at Cosmos. She has a BSc (Honours) in chemistry and science communication, and an MSc in science communication, both from the Australian National University.

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‘Almost all crops today have been changed from their original form’: National Academies of Sciences says GMOs just most recent form of food genetic modification

National Academies of Sciences Engineering and Medicine | May 3, 2022

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Credit: Mary Evans Picture Library
Credit: Mary Evans Picture Library

This article or excerpt is included in the GLP’s daily curated selection of ideologically diverse news, opinion and analysis of biotechnology innovation. It is posted under Fair Use guidelines.

People have been changing plants for thousands of years. Humans started farming more than 10,000 years. Agriculture began in Mesopotamia, in the region we now call the Middle East. At first, people took the seeds of wild plants and put them in places where they would grow well and be easier to harvest. Soon, people noticed that some plants performed better than others, and they kept the seeds of the best ones to plant the next year. As people did this year after year, farmed crops slowly became different from their wild relatives. This process is often called domestication.

The choices early farmers made about which seeds to plant were driven by many of the same factors that influence choices made about seeds today. Many wild plants naturally produce toxins that act as a defense against pests, and people made seed choices so that many crops today are tasty, nutritious, and easy to digest. Farmers want plants that are easier to harvest and produce more fruit, vegetables, grains, fiber, or oil. They also look for plants that can withstand disease, pests, flooding, drought and other problems.

Over thousands of years, people grew many types of crops, brought them to new areas of the world, and continued to change the plants to suit their needs.

Methods for changing plants expanded as science and technology advanced

In the 1800s, Gregor Mendel and others made discoveries about how parents pass traits to their offspring. This new understanding helped people produce new varieties of plants with useful qualities using selective breeding. In this method, two plants with desirable traits are deliberately mated so the next generation of plants will have these characteristics. As experiments in plant breeding continued, people learned how to breed plants together to create hybrids with certain traits. For example, hybrid types of corn, wheat, and rice were bred that produce more grain per plant and that can be grown in narrow rows in a field. Farmers are then able to harvest more grain using the same amount of land.

In the 1930s, people found that applying radiation or chemicals to a seed caused plants to have traits different from their parents. This is because radiation and certain chemicals can cause changes in the genes of plants, which determine what characteristics the plant will have. The seeds with the most useful traits caused by these genetic changes were then grown and used to breed new varieties of crops. Today, hundreds of varieties of more than 100 crops that we grow and eat were developed using these means, including many types of rice, wheat, and barley.

With the discovery of the structure of DNA in 1953 and other advances in understanding how genes work, scientists began to explore other ways to improve plants. By the 1980s, scientists were able to identify specific bits of DNA called genetic markers that are associated with particular traits. By knowing what genetic markers to look for, marker assisted breeding speeds up the breeding process by allowing scientists to know whether a plant will have the desired trait even before it is grown.

For most of history, improving plants depended on choosing two parent plants of similar types or varieties that are able to breed with each other. In the 1980s, scientists also invented ways to create new traits by combining the genes of different kinds of plants, as well as DNA from other organisms, including bacteria and viruses. These new plants carry “recombinant” DNA and are sometimes referred to as Genetically engineeredtransgenicgenetically modified organisms (GMOs), or bioengineered. More than a dozen food crops with traits introduced through recombinant DNA are grown in the world today.

In the 2010s, gene editing was developed, allowing scientists to directly change a plant’s genes without having to use the DNA from another plant or other organism. A few such crops are grown today, including gene-edited soybeans that produce soybean oil with a healthier balance of fats.

Almost all crops today have been changed from their original form

Since people have been farming for such a long time, nearly all crops grown today have been genetically improved, whether through domestication, selective breeding, hybridization, radiation or chemicals, or changes made directly to plant genes by humans.

Scientists and growers continue to improve methods for making crops with certain traits. For example, people are working to create crops that can better withstand droughts, which are becoming more common as the climate changes.

A version of this article was posted at National Academies of Sciences, Engineering, and Medicine and is used here with permission. Find the National Academies of Sciences on Twitter @theNASciences

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When will CRISPR gene editing be widely adopted in farming — and what are the blockages?

Ferdinand Los | April 20, 2022

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Credit: Pete Reynolds
Credit: Pete Reynolds

This article or excerpt is included in the GLP’s daily curated selection of ideologically diverse news, opinion and analysis of biotechnology innovation.

If you’re involved in animal or plant sciences, you’ve been reading about CRISPR technology for many years. Ranging from the promise to solve major societal issues to a Nobel prize, CRISPR has been making headlines.

Here’s the thing: it has amazing potential and we’re so close to seeing some of that potential come to life, but it has been a long road.

For any emerging technology, from discovery to actually becoming a tool that can be used on a large scale, there are many steps and obstacles. CRISPR is no different. For our company and many others there have been steep learning curves and challenges to get us to where we are today.

CRISPR gene editing is predicted to grow substantially by 2030.
Credit: Emergen Research

Policymakers, consumers and farmers

One of the biggest and most critical first steps, outside of technical challenges, was—and is—consumer acceptance and explaining this technology to policymakers. Over the first several years, we spent a lot of time educating potential customers of what this means for them.

For farmers, the advantage is obvious. We can help them increase yield potentials, for example through defensive traits such as disease tolerance. For consumers, it took more discussion about what this means for them, but it has become clear they are generally quite open to the introduction of beneficial traits, for example that help cope with environmental challenges of farming, prevent food allergies, and so on.

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From a policy perspective, policy makers have been working to create an understanding about CRISPR, its safety and its benefits and we now see legislation evolving worldwide. More and more countries are welcoming CRISPR and gene-edited technologies with open arms: The U.S. is finalizing regulation that would allow gene-editing technology to be considered a conventional crop, under the condition that the outcome could eventually be achieved by conventional breeding. Several countries in South America recently finalized similar regulation. And in recent months, the UK, Switzerland and China have all signaled to start taking legislative steps towards regulating CRISPR-edited crops as non-GMO. (More information on the current status of CRISPR regulation globally.)

Judging by these changes I think that the message has largely landed in the market now that CRISPR breeding is way faster than traditional breeding and enables types of breeding that would be impossible with traditional breeding, in a non-transgenic fashion.

Cisgenic transfer occurs within the same plant or family. Transgenes are from other sources. Credit: Schouten et al.

We’re seeing that people do understand what’s going on. You can see that that on the consumer side, largely people look at this much more favorably than they do at the traditional GMO (transgenic) crops.

Research versus reputation

However, communication is still needed. Many companies are using this technology in R&D and breeding, but few are actually marketing products made using CRISPR. We see many companies holding back on putting crops into the market because they still consider consumer acceptance as a risk and fear for their brands’ reputations.

As objective as the profit motive and science can be, consumers and governments approach CRISPR with skepticism and questions.

We’re here to continue developing the technology as well as continue the conversation with researchers, breeders, seed companies, policymakers, and other organizations with an interest in molecular breeding so that new crop varieties developed with CRISPR can benefit from a faster route-to-market that is both democratized and beneficial to everyone.

Ferdinand Los is CSO of Hudson River Biotechnology.  Ferdinand holds advanced degrees in sciences including  a PhD from the University of California San Diego and post-doctoral work at Colombia University. You can check out Hudson River Biotechnology on Twitter @HudsonRiverBio1

A version of this article was posted to Seed World and is used here with permission. You can check out Seed World on Twitter @SeedWorldGroup

The GLP featured this article to reflect the diversity of news, opinion and analysis. The viewpoint is the author’s own. The GLP’s goal is to stimulate constructive discourse on challenging science issues.

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South Africa should rethink regulations on genetically modified plants

February 15, 2022 9.12am EST

Authors

  1. James R LloydAssociate Professor, Stellenbosch University
  2. Dave BergerProfessor in Molecular Plant Pathology, University of Pretoria
  3. Priyen PillaySenior Researcher, Council for Scientific and Industrial Research

Disclosure statement

James R Lloyd receives funding from the National Research Foundation, South Africa.

Dave Berger receives funding from the National Research Foundation, South Africa and The Maize Trust, South Africa.

Dr Priyen Pillay receives funding from the National Research Foundation, South Africa and the Department of Science & Innovation, South Africa.

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New technologies can bolster the production of important crops to feed billions of people. Shutterstock

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Food security is a global priority – and it is becoming more urgent in the face of climate change, which is already affecting crop productivity. One way to improve food security is to increase crop yields.

But this is not easy. Research has shown that in the past two decades plant breeders have been unable to increase yields of staple crops at the rate at which the world’s population is growing.

New technologies are needed to achieve this rate. Over the past decade several novel technologies have been developed. These are known as New Breeding Techniques and have the potential to hugely help in growing efforts.

Genome editing is one such technique. It allows the precise editing of genomes – that is, the genetic information an organism contains. Scientists worldwide have embraced the technology. And countries that adopted New Breeding Techniques early have seen a significant increase in the development of locally relevant products. Current crops under development include ones resistant to specific diseases and insect pests, that are healthier to eat or which are tolerant of drought or heat stress.

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Both small, micro and medium enterprises and the public sector in these countries have been involved in developing and using genome edited crops. This should translate to improved economic growth and employment opportunities.


Read more: What is CRISPR, the gene editing technology that won the Chemistry Nobel prize?


Whatever approach a country chooses, it must be underpinned by regulation. This ensures a framework for the introduction of new products that benefit consumers and stimulate the bio-economy in a sustainable manner.

South Africa’s authorities have taken what we think is an unfortunate approach to regulating genome-edited plants. In October 2021 the government classified genome-edited plants as genetically modified crops. This is based on its interpretation of the definition of a genetically modified organism in a 25-year-old piece of legislation rather than on recent science-based risk analysis considerations.

As experts in plant biotechnology we fear that this regulatory approach will greatly inhibit the development of improved crops for South African farmers. It will place an unnecessary regulatory burden on bio-innovators. This will discourage local investment for in-house research and development, as well as projects in the public sector. Local entrepreneurs who aim to enhance local crops’ climate resilience or to develop speciality products for niche markets through genome editing will be thwarted by the need to raise disproportionate funding to fulfil current regulations.

A technological timeline

Crop plants are improved by generating genetic variation that leads to beneficial traits. Plant breeders traditionally achieved this by crossing different varieties of the same plant species. These approaches alter many genes; the result is that traditionally-bred plants contain both advantageous and deleterious traits. Removing disadvantageous traits before the crop can be commercialised is a costly, time-consuming process.

In the 1980s, transgenic genetic modification technologies were developed. These rely on pieces of DNA from one species being integrated into the genome of a crop. Such genetically modified (GM) plants are highly regulated internationally. In South Africa the legislation governing these plants came into force in 1999. The use of GM technology in South Africa – and other countries – has been highly successful.

For example, it has led to South Africa doubling maize productivity, making it a net exporter of this commodity. This contributes to food security and also generates foreign income, which reduces the country’s trade deficit.

But the regulations governing GM plants are onerous: only large agricultural biotechnology companies have the resources to commercialise them. This is done to the eliminate risk that GM plants containing new DNA are harmful for health or to the environment.

Because of this, all GM plants licensed for commercial use in South Africa come from a small number of international companies. Not a single locally developed product has been commercialised during the past three decades, despite South Africa being an early adopter of the technology. This hampers the development of novel crops and the improvement of traditional crops, especially for emerging and subsistence farmers in sub-Saharan Africa.

That’s why newer tools like genome editing are so exciting. They can be used to introduce genetic variation for crop improvement in a fraction of the time it would take using conventional methods. Some forms of genome editing are transgenic in nature, while others aren’t because they don’t involve the insertion of foreign DNA into a plant.

This approach mimics the effect of traditional plant breeding, but in a highly targeted manner so that only advantageous traits are introduced. For example, genome editing is being used to produce peanuts, soybean and wheat that do not produce allergens.

It’s working well. Despite the technology only being available for a decade, some crops produced using genome editing are already on the market in some countries, including soybean and tomatoes which are healthier for human consumption.

A proposed regulatory approach

Regulatory authorities around the world have taken either a process- or a product-based approach to regulating GM crop safety. A process-based approach examines how the crop was produced; a product-based approach examines the risks and benefits of the GM crop on a case-by-case basis.

We believe that a product-based approach makes most sense. This is because a process-based approach could lead to the strange situation where two identical plants are governed by very different regulations, just because they were produced by different methods. The added regulatory burden imposed by this approach will also hamper innovation in developing new crops.

Our approach would mean that any plant with extra DNA inserted into the genome would be governed as a GM plant. Plants with no extra DNA added and that are indistinguishable from conventionally bred organisms should be regulated like a conventionally produced crop.

This is the most rational way to regulate these different types of organisms, as it adheres to the principles of science-based risk analysis and good governance.

Many countries, among them ArgentinaChinaJapanthe USAustraliaBrazil and Nigeria, have taken this approach.

Science-based risk analysis should return to the heart of regulation: concrete risk thresholds should define regulatory triggers.

T

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The tomatoes at the forefront of a food revolution Share using EmailShare on TwitterShare on FacebookShare on Linkedin(Image credit: Arif Ali/AFP/Getty Images)

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More than 180 million tons of tomatoes are produced globally each year, but the crop is sensitive to changes in the climate (Credit: Arif Ali/AFP/Getty Images)

By Marta Zaraska8th December 2021As global temperatures increase and extreme weather events become more common, can gene editing help to tweak our food plants so they can cope with the changes?A

At first glance, it looked like any other plant that can be found growing in the corners of offices or on the windowsills of university laboratories. But this particular tomato plant, grown in 2018 at the University of Minnesota, was different. The bushy tangle of elongated leaves and small red fruits were characteristic of a wild species of tomato plant native to Peru and Ecuador called Solanum pimpinellifolium, also known as the red currant tomato. A closer inspection, however, made the plant’s uniqueness more apparent.

This particular plant was more compact, with fewer branches but more fruits than the wild tomato. Its fruits were also a little darker than was usual, a sign of increased lycopene – an antioxidant linked to a lower risk of cancer and heart disease. It had, in fact, been designed that way.

The plant was created by geneticist Tomas Cermak and his colleagues with the use of Crispr gene editing, a Nobel Prize-winning technology which works like a “cut and paste” tool for genetic material. The technique is now revolutionising agriculture and helping create crops for the future.ADVERTISEMENT

Cermak himself is on a mission to find a perfect tomato, one that would be easy to cultivate, nutritious and tasty, yet more adaptable to a changing climate. “The ideal plant would be resistant to all forms of stress — heat, cold, salt and drought, as well as to pests,” he says.

Climate change spells trouble for many crops, and tomatoes are no exception. Tomatoes don’t like heat, growing best between 18C (64F) and 25C (77F). Cross either side of that threshold and things start going downhill: pollen doesn’t form properly, the flowers don’t form into berries in the way they should. Once the mercury goes over 35C (95F), yields begin to collapse. A 2020 study showed that by mid-21st Century up to 66% of land in California historically used for growing tomatoes may no longer have temperatures appropriate for the crop. Other modelling studies suggest that by 2050 large swaths of land in Brazil, sub-Saharan Africa, India and Indonesia will also no longer have optimal climate for cultivation of tomatoes.

Story continues belowSolanum pimpinellifolium is a wild tomato found in Peru and Ecuador which bears fruit the size of currants (Credit: Alamy)

Solanum pimpinellifolium is a wild tomato found in Peru and Ecuador which bears fruit the size of currants (Credit: Alamy)

Of course, as average temperatures rise, other, previously too chilly regions, may become tomato-friendly. Yet observations in Italy show that weather extremes are something to consider, too. The 2019 growing season in northern Italy was marred by hail, strong winds, unusually high rainfall, and both exceptional frost and exceptional heat. The result was stressed tomato plants and poor harvests.

And there is more. Water scarcity, which forces farmers to use lower quality irrigation water, often containing salt, leads to increases in soil salinity – something commercial tomato cultivars don’t like. Higher ozone levels, meanwhile, make tomatoes more susceptible to diseases such as bacterial leaf spot.

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That’s all troubling, especially considering that tomatoes are currently the largest horticultural crop in the world – humanity produces 182 million tons of the fruit every year, equivalent to the weight of almost 32 Great Pyramids of Giza. What’s more, our appetites for tomatoes are growing fast – over the last 15 years global production of tomatoes rose by more than 30%.

Besides being humanity’s favourite fruit, tomatoes also happen to be a model crop: they are fast to grow, easy to breed and relatively simple to manipulate on a genetic level. “There is more funding available for research than there is for other plant species to develop resources like genome sequences, genetic engineering, and gene editing for tomato,” says Joyce Van Eck, plant geneticist at the Boyce Thompson Institute in New York. Taken together, this makes tomatoes perfect for study of novel gene editing technologies such as Crispr, which could bring us many climate-adaptive crops in the near future.

Once the climate-smart genes such as these are identified, they can be targeted using Crispr to delete certain unwanted genes, to tune others or insert new ones

Crispr is a molecular toolbox scientists have repurposed from bacteria – when bacteria are attacked by viruses, they capture and cut the viral DNA to prevent the aggressor from being able to replicate and so fight it off. In use in plants since 2013, Crispr now allows researchers to modify genome with extreme precision and accuracy to obtain traits they desire. You can insert genes, delete them, and create targeted mutations. In non-human animals Crispr is being used for the study of human disease models, for improving livestock, and could even potentially be used to resurrecting extinct species. In plants, it can help create better, tastier, more nutritious and more resistant crops.

The first step is finding the right genes to target. “We need to identify the genes responsible or involved in being able to withstand abiotic and biotic stress because otherwise we cannot alter, modify or knock them out by using gene editing,” says Richard Visser, plant geneticist at Wageningen University, the Netherlands.

Domesticating crops, tomatoes included, has led to a huge loss of genetic diversity. Modern commercial cultivars may be fast to grow and easy to harvest, but genetically speaking they are plain vanilla. Just four highly homogenised crops – soybeans, rice, wheat and corn – dominate global agriculture, accounting for more than half of all the world’s agricultural land.

In contrast, their wild cousins – as well as so-called landraces (traditional varieties adapted to specific locations) – are a treasure box of genetic diversity. This is why scientists now search this genetic pool to identify traits that can be reintroduced into commercial plants – a process much helped by fast-dropping costs of DNA-sequencing technologies.As climate change alters rainfall patterns, new varieties of drought resistant crops will be needed in areas that struggle with water shortages (Credit: Janos Chiala/Getty Images)

As climate change alters rainfall patterns, new varieties of drought resistant crops will be needed in areas that struggle with water shortages (Credit: Janos Chiala/Getty Images)

One 2021 study looked at the genome of Solanum sitiens – a wild tomato species which grows in the extremely harsh environment of the Atacama Desert in Chile, and can be found at altitudes as high as 3,300m (10,826ft). The study identified several genes related to drought-resistance in Solanum sitiens, including one aptly named YUCCA7 (yucca are draught-resistant shrubs and trees popular as houseplants).

They are far from the only genes that could be used to give the humble tomato a boost. In 2020 Chinese and American scientists performed a genome-wide association study of 369 tomato cultivars, breeding lines and landraces, and pinpointed a gene called SlHAK20 as crucial for salt tolerance.

Once the climate-smart genes such as these are identified, they can be targeted using Crispr to delete certain unwanted genes, to tune others or insert new ones. This has recently been done with salt tolerance, resistance to various tomato pathogens, and even to create dwarf plants which could withstand strong winds (another side effect of climate change). However, scientists such as Cermak go even further and start at the roots – they are using Crispr to domesticate wild plant species from scratch, “de novo” in science speak. Not only can they achieve in a single generation what previously took thousands of years, but also with a much greater precision.

De novo domestication of Solanum pimpinellifolium was how Cermak and his colleagues at the University of Minnesota arrived at their 2018 plant. They targeted five genes in the wild species to obtain a tomato that would be still resistant to various stresses, yet more adapted to modern commercial farming – more compact for easier mechanical harvesting, for example. The new plant also had larger fruits than the wild original.

“The size and weight was about double,” Cermak says. Yet this still wasn’t the ideal tomato he strives to obtain – for that more work needs to be done. “By adding additional genes, we could make the fruit even bigger and more abundant, increase the amount of sugar to improve taste, and the concentration of antioxidants, vitamin C and other nutrients,” he says. And, of course, resistance to various forms of stress, from heat and pests to draught and salinity.Some scientists believe that Crispr's ability to accurately edit the traits of plants could usher in a new green revolution (Credit: Sean Gallup/Getty Images)

Some scientists believe that Crispr’s ability to accurately edit the traits of plants could usher in a new green revolution (Credit: Sean Gallup/Getty Images)

De novo domestication could also make orphan crops more attractive. These are plants that are grown on a limited scale, but have a great potential to help food security. Groundcherry, a wild cousin of tomatoes which produces subtly sweet berries, is one such crop that has been recently domesticated with Crispr technology. In the near future, de novo domestication could bring crops as cowpea, sorghum and teff — all cereals native to Africa – to a far wider audience around the world. Crispr is also now being used to improve various other plants, from bananas and grapes to rice and cucumbers.

Some scientists believe that Crispr gene-editing marks the beginning of the second green revolution to help feed the fast-growing human population. Yet although the technology does hold a great promise for crop improvement, it’s “not a miracle potion”, Visser says. There are still technical hurdles to address.

“Efficiency of editing can be a problem in some crop species,” Van Eck says. As opposed to diploid plants like tomato (which have paired chromosomes), those that have more than two paired sets of chromosomes (known as polyploid, like wheat), are much harder to work on. “You basically have more copies of a gene in polyploids that need to be affected by Crispr than in a diploid,” Van Eck adds.Scientists Emmanuelle Charpentier and Jennifer Doudna won the Nobel Prize in Chemistry for their discovery of the Crispr-Cas9 genetic scissors (Credit: Reuters/Eloy Alonso/Alamy)

Scientists Emmanuelle Charpentier and Jennifer Doudna won the Nobel Prize in Chemistry for their discovery of the Crispr-Cas9 genetic scissors (Credit: Reuters/Eloy Alonso/Alamy)

Regulation and social acceptance are also an issue. Crispr modified plants can be “transgene-free” – meaning that unlike traditional genetically modified (GM) crops, those created by Crispr technology do not contain DNA from a different species (ie transgenic) – that’s because the technology either involves simply deleting genes, or may involve inserting genes from a different varieties of the same species (as is being done with tomatoes).

Yet, the few existing studies on acceptance of Crispr-edited food products show a mixed picture. In a cross-country survey conducted in USA, Canada, Belgium, France and Australia, people perceived Crispr-edited and GM food similarly. However, in a 2020 Canadian study, consumers were more willing to accept Crispr-edited foods.

And then, there is the law. Although in 2016 Crispr-edited mushrooms fell into a legal loophole in the US and escaped regulation, Europe’s highest court decided in 2018 that gene-edited crops should be subject to the same stringent regulations that govern conventional GM organisms.

For Cermak’s climate-smart “ideal tomato”, such legal hurdles paired with consumer hesitance, could prove a major obstacle.

* This article was updated on 7 January 2022 to change Joyce Van Eck’s affiliation from Cornell University to the Boyce Thompson Institute, where she is primarily based.

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Genetic strategy reverses insecticide resistance

Date: January 14, 2022Source: University of California – San Diego Summary: Using CRISPR/Cas9 technology, scientists have genetically engineered a method to reverse insecticide resistance. The gene replacement method offers a new way to fight deadly malaria spread and reduce the use of pesticides that protect valuable food crops.Share: FULL STORY


Insecticides play a central role in efforts to counter global impacts of mosquito-spread malaria and other diseases, which cause an estimated 750,000 deaths each year. These insect-specific chemicals, which cost more than $100 million to develop and bring to market, also are critical to controlling insect-driven crop damage that poses a challenge to food security.

But in recent decades many insects have genetically adapted to become less sensitive to the potency of insecticides. In Africa, where long-lasting insecticide-treated bed nets and indoor spraying are major weapons in the fight against malaria, many species of mosquitoes across the continent have developed insecticide resistance that reduces the efficacy of these key interventions. In certain areas climate change is expected to exacerbate these problems.

University of California San Diego biologists have now developed a method that reverses insecticide resistance using CRISPR/Cas9 technology. As described in Nature Communications, researchers Bhagyashree Kaduskar, Raja Kushwah and Professor Ethan Bier with the Tata Institute for Genetics and Society (TIGS) and their colleagues used the genetic editing tool to replace an insecticide-resistant gene in fruit flies with the normal insecticide-susceptible form, an achievement that could significantly reduce the amount of insecticides used.

“This technology also could be used to increase the proportion of a naturally occurring genetic variant in mosquitoes that renders them refractory to transmission or malarial parasites,” said Bier, a professor of Cell and Developmental Biology in UC San Diego’s Division of Biological Sciences and senior author of the paper.

The researchers used a modified type of gene-drive, a technology that uses CRISPR/Cas9 to cut genomes at targeted sites, to spread specific genes throughout a population. As one parent transmits genetic elements to their offspring, the Cas9 protein cuts the chromosome from the other parent at the corresponding site and the genetic information is copied into that location so that all offspring inherit the genetic trait. The new gene-drive includes an add-on that Bier and his colleagues previously engineered to bias the inheritance of simple genetic variants (also known as alleles) by also at the same time cutting an undesired genetic variant (e.g., insecticide resistant) and replacing it with the preferred variant (e.g., insecticide susceptible).

In the new study, the researchers employed this “allelic drive” strategy to restore genetic susceptibility to insecticides, similar to insects in the wild prior to their having developed resistance. They focused on an insect protein known as the voltage-gated sodium channel (VGSC) which is a target for a widely used class of insecticides. Resistance to these insecticides, often called the knockdown resistance, or “kdr,” results from mutations in the vgsc gene that no longer permit the insecticide to bind to its VGSC protein target. The authors replaced a resistant kdr mutation with its normal natural counterpart that is susceptible to insecticides.

Starting with a population consisting of 83% kdr (resistant) alleles and 17% normal alleles (insecticide susceptible), the allelic drive system inverted that proportion to 13% resistant and 87% wild-type in 10 generations. Bier also notes that adaptions conferring insecticide resistance come with an evolutionary cost, making those insects less fit in a Darwinian sense. Thus pairing the gene drive with the selective advantage of the more fit wild-type genetic variant results in a highly efficient and cooperative system, he says.

Similar allelic drive systems could be developed in other insects, including mosquitoes. This proof-of-principle adds a new method to pest- and vector-control toolboxes since it could be used in combination with other strategies to improve insecticide-based or parasite-reducing measures to drive down the spread of malaria.

“Through these allelic replacement strategies, it should be possible to achieve the same degree of pest control with far less application of insecticides,” said Bier. “It also should be possible to design self-eliminating versions of allelic drives that are programmed to act only transiently in a population to increase the relative frequency of a desired allele and then disappear. Such locally acting allelic drives could be reapplied as necessary to increase the abundance of a naturally occurring preferred trait with the ultimate endpoint being no GMO left in the environment.”

“An exciting possibility is to use allelic drives to introduce novel versions of the VGSC that are even more sensitive to insecticides than wild-type VGSCs,” suggested Craig Montell (UC Santa Barbara), a co-author on this study. “This could potentially allow even lower levels of insecticides to be introduced into the environment to control pests and disease vectors.”

The study’s authors are: Bhagyashree Kaduskar (UC San Diego and Tata Institute for Genetics and Society), Raja Babu Singh Kushwah (UC San Diego and Tata Institute for Genetics and Society), Ankush Auradkar (UC San Diego), Annabel Guichard (UC San Diego and Tata Institute for Genetics and Society), Menglin Li (UC Santa Barbara), Jared Bennett (UC Berkeley), Alison Henrique Ferreira Julio, John Marshall (UC Berkeley), Craig Montell (UC Santa Barbara) and Ethan Bier (UC San Diego and Tata Institute for Genetics and Society).


Story Source:

Materials provided by University of California – San Diego. Original written by Mario Aguilera. Note: Content may be edited for style and length.


Journal Reference:

  1. Bhagyashree Kaduskar, Raja Babu Singh Kushwah, Ankush Auradkar, Annabel Guichard, Menglin Li, Jared B. Bennett, Alison Henrique Ferreira Julio, John M. Marshall, Craig Montell, Ethan Bier. Reversing insecticide resistance with allelic-drive in Drosophila melanogasterNature Communications, 2022; 13 (1) DOI: 10.1038/s41467-021-27654-1

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Viewpoint: How Bangladesh can use genetic engineering to improve food security

Asma Binti HafizSumon Chandra Shell | Academia | January 10, 2022

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Bt infused eggplants, 'brinjal' are a critical crop for Bangladesh. Credit: Arif Hossain
Bt infused eggplants, ‘brinjal’ are a critical crop for Bangladesh. Credit: Arif Hossain

This article or excerpt is included in the GLP’s daily curated selection of ideologically diverse news, opinion and analysis of biotechnology innovation. It is posted under Fair Use guidelines.

Bangladesh has declared self-sufficiency in food in 2013 with a population of 150 million and continued to maintain the status up till this date as the population has increased by another twenty million. Follow the latest news and policy debates on agricultural biotech and biomedicine? Subscribe to our newsletter.SIGN UP

Genetic Engineering is a vital tool for Bangladesh to secure food in its true sense by meeting food needs, reducing poverty, and enhancing environmental sustainability. But, awareness and extent of knowledge and perception on genetic engineering, biotechnology, and GMOs among the people, and especially the producers, are relatively low (Nasiruddin). Here, media, agricultural universities and research institutions, NGOs, political agenda, government policies, and religious bodies have played vital roles in representing Genetic Engineering in food security.For example, bt brinjal, a GMO of Bangladesh, yields 42% higher than the local varieties and reduces 47% of the cost of applying pesticides (Ahmed et al.). But only 17% of the country’s brinjal farmers have adopted this GMO crop (The Wire)

Genetic Engineering has the potential to turn the jolty terrain of food access in Bangladesh into a plane field with sufficient, nutritious, less expensive, and equally distributed food for all the country’s people to meet their dietary needs.

This is an excerpt. Read the original post here.

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