Published by the CT Mirror on May 28th, 2018
To feed the burgeoning human population, it is vital that the world figures out ways to boost food production.
Increasing crop yields through conventional plant breeding is inefficient – the outcomes are unpredictable and it can take years to decades to create a new strain. On the other hand, powerful genetically modified plant technologies can quickly yield new plant varieties, but their adoption has been controversial. Many consumers and countries have rejected GMO foods even though extensive studies have proved they are safe to consume.
But now a new genome editing technology known as CRISPR may offer a good alternative.
I’m a plant geneticist and one of my top priorities is developing tools to engineer woody plants such as citrus trees that can resist the greening disease, Huanglongbing (HLB), which has devastated these trees around the world. First detected in Florida in 2005, the disease has decimated the state’s $9 billion citrus crop, leading to a 75 percent decline in its orange production in 2017. Because citrus trees take five to 10 years before they produce fruits, our new technique – which has been nominated by many editors-in-chief as one of the groundbreaking approaches of 2017 that has the potential to change the world – may accelerate the development of non-GMO citrus trees that are HLB-resistant.
GENETICALLY MODIFIED VS. GENE EDITED
You may wonder why the plants we create with our new DNA editing technique are not considered GMO? It’s a good question.
Genetically modified refers to plants and animals that have been altered in a way that wouldn’t have arisen naturally through evolution. A very obvious example of this involves transferring a gene from one species to another to endow the organism with a new trait – like pest resistance or drought tolerance.
But in our work, we are not cutting and pasting genes from animals or bacteria into plants. We are using genome editing technologies to introduce new plant traits by directly rewriting the plants’ genetic code.
This is faster and more precise than conventional breeding, is less controversial than GMO techniques, and can shave years or even decades off the time it takes to develop new crop varieties for farmers.
There is also another incentive to opt for using gene editing to create designer crops. On March 28, 2018, U.S. Secretary of Agriculture Sonny Perdue announced that the USDA wouldn’t regulate new plant varieties developed with new technologies like genome editing that would yield plants indistinguishable from those developed through traditional breeding methods. By contrast, a plant that includes a gene or genes from another organism, such as bacteria, is considered a GMO. This is another reason why many researchers and companies prefer using CRISPR in agriculture whenever it is possible.
CHANGING THE PLANT BLUEPRINT
The gene editing tool we use is called CRISPR – which stands for “Clustered Regularly Interspaced Short Palindromic Repeats” – and was adapted from the defense systems of bacteria. These bacterial CRISPR systems have been modified so that scientists like myself can edit the DNA of plants, animals, human cells and microorganisms. This technology can be used in many ways, including to correct genetic errors in humans that cause diseases, to engineer animals bred for disease research, and to create novel genetic variations that can accelerate crop improvement.
To use CRISPR to introduce a useful trait into a crop plant, we need to know the genes that control a particular trait. For instance, previous studies have revealed that a natural plant hormone called gibberellin is essential for plant height. The GA20-ox gene controls the quantity of gibberellin produced in plants. To create a breed of “low mowing frequency” lawn grass, for example, we are editing the DNA – changing the sequence of the DNA that makes up gene – of this plant to reduce the output of the GA20-ox gene in the selected turf grass. With lower gibberellin, the grass won’t grow as high and won’t need to be mowed as often.
The CRISPR system was derived from bacteria. It is made up of two parts: Cas9, a little protein that snips DNA, and an RNA molecule that serves as the template for encoding the new trait in the plant’s DNA.
To use CRISPR in plants, the standard approach is to insert the CRISPR genes that encode the CRISPR-Cas9 “editing machines” into the plant cell’s DNA. When the CRISPR-Cas9 gene is active, it will locate and rewrite the relevant section of the plant genome, creating the new trait.
But this is a catch-22. Because to perform DNA editing with CRISPR/Cas9 you first have to genetically alter the plant with foreign CRISPR genes – this would make it a GMO.
A NEW STRATEGY FOR NON-GMO CROPS
For annual crop plants like corn, rice and tomato that complete their life cycles from germination to the production of seeds within one year, the CRISPR genes can be easily eliminated from the edited plants. That’s because some seeds these plants produce do not carry CRISPR genes, just the new traits.
But this problem is much trickier for perennial crop plants that require up to 10 years to reach the stage of flower and seed production. It would take too long to wait for seeds that were free of CRISPR genes.
My team at the University of Connecticut and my collaborators at Nanjing Agricultural University, Jiangsu Academy of Agricultural Sciences, University of Florida, Hunan Agricultural University and University of California-San Diego have recently developed a convenient, new technique to use CRISPR to reliably create desirable traits in crop plants without introducing any foreign bacterial genes.
We first engineered a naturally occurring soil microbe, Agrobacterium, with the CRIPSR genes. Then we take young leaf or shoot material from plants and mix them in petri dishes with the bacteria and allow them to incubate together for a couple of days. This gives the bacteria time to infect the cells and deliver the gene editing machinery, which then alters the plant’s genetic code.
In some Agrobacterium infected cells, the Agrobacterium basically serves as a Trojan horse, bringing all the editing tools into the cell, rather than engineering plants to have their own editing machinery. Because the bacterial genes or CRISPR genes do not become part of the plant’s genome in these cells – and just do the work of gene editing – any plants derived from these cells are not considered a GMO.
After a couple of days, we can cultivate plants from the edited plant cells. Then it take several weeks or months to grow an edited plant that could be planted on a farm. The hard part is figuring out which plants are successfully modified. But we have a solution to this problem too and have developed a method that takes only two weeks to identify the edited plants.
GENETICALLY DESIGNED LAWNS
One significant difference between editing plants versus human cells is that we are not as concerned about editing typos. In humans, such errors could cause disease, but off-target mutations in plants are not a serious concern. A number of published studies reported low to negligible off-target activity observed in plants when compared to animal systems.
Also, before distributing any plants to farmers for planting in their field, the edited plants will be carefully evaluated for obvious defects in growth and development or their responses to drought, extreme temperatures, disease and insect attacks. Further, DNA sequencing of edited plants once they have been developed can easily identify any significant undesirable off-target mutations.
In addition to citrus, our technology should be applicable in most perennial crop plants such as apple, sugarcane, grape, pear, banana, poplar, pine, eucalyptus and some annual crop plants such as strawberry, potato and sweet potato that are propagated without using seeds.
We also see a role for genome editing technologies in many other plants used in the agricultural, horticultural and forestry industries. For example, we are creating lawn grass varieties that require less fertilizer and water. I bet you would like that too.
January 24, 2018
Humankind is on the verge of a genetic revolution that holds great promise and potential. It will change the ways food is grown, medicine is produced, animals are altered and will give rise to new ways of producing plastics, biofuels and chemicals.
Many object to the genetic revolution, insisting we should not be ‘playing God’ by tinkering with the building blocks of life; we should leave the genie in the bottle. This is the view held by many opponents of GMO foods. But few transformative scientific advances are widely embraced at first. Once a discovery has been made and its impact widely felt it is impossible to stop despite the pleas of doubters and critics concerned about potential unintended consequences. Otherwise, science would not have experienced great leaps throughout history—and we would still be living a primitive existence.
Gene editing of humans and plants—a revolutionary technique developed just a few years ago that makes genetic tinkering dramatically easier, safer and less expensive—has begun to accelerate this revolution. University of California-Berkeley biochemist Jennifer Doudna, one of the co-inventors of the CRISPR technique::
Within the next few years, this new biotechnology will give us higher-yielding crops, healthier livestock, and more nutritious foods. Within a few decades, we might well have genetically engineered pigs that can serve as human organ donors…we are on the cusp of a new era in the history of life on earth—an age in which humans exercise an unprecedented level of control over the genetic composition of the species that co-inhabit our planet. It won’t be long before CRISPR allows us to bend nature to our will in the way that humans have dreamed of since prehistory.
The four articles in this series will examine the dramatic changes that gene editing and other forms of genetic engineering will usher in.
Great advances likely for GE foods
Despite the best efforts of opponents, GE crops have become so embedded and pervasive in the food systems—even in Europe which has bans in place on growing GMOs in most countries—that it is impossible to dislodge them without doing serious damage to the agricultural sector and boosting food costs for consumers.
Even countries which ban the growing of GMOs or who have such strict labeling laws that few foods with GE ingredients are sold in supermarkets are huge consumers of GE products.
Europe is one of the largest importers of GMO feed in the world. Most of the meat we consume from cattle, sheep, goats, chickens, turkeys, pigs and fish farms are fed genetically modified corn, soybeans and alfalfa.
North America, much of South America and Australia are major consumers of foods grown from GE seeds. Much of the corn oil, cotton seed oil, soybean oil and canola oil used for frying and cooking, and in salad dressings and mayonnaise is genetically modified. GM soybeans are used to make tofu, miso, soybean meal, soy ice cream, soy flour and soy milk. GM corn is processed into corn starch and corn syrup and is used to make whiskey. Much of our sugar is derived from GM sugar beets and GE sugarcane is on the horizon. Over 90 percent of the papaya grown in Hawaii has been genetically modified to make it resistant to the ringspot virus. Some of the squash eaten in the US is made from GM disease-resistant seeds and developing countries are field testing GM disease-resistant cassava.
Many critics of GE in agriculture focus on the fact that by volume most crops are used in commodity food manufacturing, specifically corn and soybeans. One reason for that is the high cost of getting new traits approved. Indeed, research continues on commodity crops, although many of the scientists work for academia and independent research institutes.
For example, in November 2016, researchers in the UK were granted the authority to begin trials of a genetically engineered wheat that has the potential to increase yields by 40 percent. The wheat, altered to produce a higher level of an enzyme critical for turning sunlight and carbon dioxide into plant fuel, was developed in part by Christine Raines, the Head of the School of Biological Sciences at the University of Essex.
Genetic engineering and nutrition enhancement
A new generation of foods are now on the horizon, some as the result of new breeding techniques (NBTs), such as gene editing. Many of these foods will be nutritionally fortified, which will be critical to boosting the health of many of the poorest people in developing nations and increase yields.
Golden rice is a prime example of such a nutrition-enhanced crop. It is genetically engineered to have high levels of beta carotene, a precursor of Vitamin A. This is particularly important as many people in developing countries suffer from Vitamin A deficiency which leads to blindness and even death. Bangladesh is expected to begin cultivation of golden rice in 2018. The Philippines may also be close to growing it.
A strain of golden rice that includes not only high levels of beta carotene but also high levels of zinc and iron could be commercialized within 5 years. “Our results demonstrate that it is possible to combine several essential micronutrients – iron, zinc and beta carotene – in a single rice plant for healthy nutrition,” said Navreet Bhullar, senior scientist at ETH Zurich, which developed the rice.
The Science in the News group at Harvard University discussed some of the next generation foods.
Looking beyond Golden Rice, there are a large number of biofortified staple crops in development. Many of these crops are designed to supply other micronutrients, notably vitamin E in corn, canola and soybeans…Protein content is also a key focus; protein-energy malnutrition affects 25% of children because many staple crops have low levels of essential amino acids. Essential amino acids are building blocks of proteins and must be taken in through the diet or supplements. So far, corn, canola, and soybeans have been engineered to contain higher amounts of the essential amino acid lysine. Crops like corn, potatoes and sugar beets have also been modified to contain more dietary fiber, a component with multiple positive health benefits.
Other vitamin-enhanced crops have been developed though they have yet to be commercialized. Australian scientists created a GE Vitamin A enriched banana, scientists in Kenya developed GE Vitamin A enhanced sorghum and plant scientists in Switzerland developed a GE Vitamin B6 enhanced cassava plant. None is near approval, however.
Scientists genetically engineered canola, a type of rapeseed, to produce additional omega-3 fatty acids. Research is being conducted on developing GM gluten free wheat and vegetables with higher levels of Vitamin E to fight heart disease.
Other more consumer-focused genetically-engineered crops that do not use transgenics, and have sailed through the approval system include:
- FDA has approved the commercialization of a GE non-browning apple—the Arctic Apple, developed by using a gene-silencing technique.
- Simplot has developed GE potatoes created using gene-silencing techniques. They are less prone to bruising and blackening, in some cases are resistant to certain diseases and also contain less asparagine which reduces the potential for acrylamide that is created when frying, baking and roasting.
Fighting plant diseases
Other products are in development that fight viruses and disease. Scientists have used genetic engineering to develop disease-resistant rice. A new plum variety resists the plum pox virus. It has not yet been commercialized. GE solutions may be the only answer to save the orange industry from citrus greening, which is devastating orange groves in Florida. GE might be utilized to curb the damage caused by stem rust fungus in wheat and diseases effecting the coffee crop.
In Africa, GE solutions could be used to combat the ravages of banana wilt and cassava brown streak disease and diseases that impact cocoa trees and potatoes. A GE bean has been developed in Brazil that is resistant to the golden mosaic virus. Researchers at the University of Florida, the University of California-Berkeley and the 2Blades Foundation have developed a disease resistant GM tomato.
Scientists at the John Innes Center in the UK are attempting to create a strain of barley capable of making its own ammonium fertilizer from nitrogen in the soil. This would be particularly beneficial to farmers who grow crops in poor soil conditions or who lack the financial resources to buy artificial fertilizers.
Peggy Ozias-Akins, a horticulture expert at the University of Georgia has developed and tested genetically-engineered peanuts that do not produce two proteins linked to intense allergens.
New Breeding Techniques
New gene editing techniques (NBTs) such as CRISPR offer great potential and face lower approval hurdles, at least for now.
- Scientists at Penn State have removed the gene that causes white button mushrooms to discolor, and the product was quickly approved.
- In 2014, scientists in China produced bread wheat resistant to powdery mildew.
- Calyxt, a biotechnology company, has developed a potato variety that prevents the accumulation of certain sugars, reducing the bitter taste associated with storage. The potato also has a lower amount of acrylamide.
- DuPont has developed a gene-edited variety of corn, which can be used to thicken food products and make adhesives.
In June, the EPA approved a new first of its kind GE corn known as SmartStaxPro, in which the plant’s genes are tweaked without transgenics to produce a natural toxin designed to kill western corn rootworm larvae. It also produces a piece of RNA that shuts down a specific gene in the larvae, thereby killing them. The new GE corn is expected to be commercialized by the end of the decade.
What could slow—or even stop—this revolution? In an opinion piece for Nature Biology, Richard B. Flavell, a British molecular biologist and former director of the John Innes Center in the UK, which conducts research in plant science, genetics and microbiology, warned about the dangers of vilifying and hindering new GE technologies:
The consequences of simply sustaining the chaotic status quo—in which GMOs and other innovative plant products are summarily demonized by activists and the organic lobby—are frightening when one considers mounting challenges to food production, balanced nutrition and poverty alleviation across the world. Those who seek to fuel the GMO versus the non-GMO debate are perpetuating irresolvable difference of opinion. …Those who seek to perpetuate the GMO controversy and actively prevent use of new technology to crop breeding are not only on the wrong side of the debate, they are on the wrong side of the evidence. If they continue to uphold beliefs against evidence, they will find themselves on the wrong side of history.
Steven E. Cerier is a freelance international economist and a frequent contributor to the Genetic Literacy Project.
Most of us don’t spend our days plowing fields or wrangling cattle. We’re part of the 99 percent of Americans who eat food but don’t produce it. Because of our intimate relationship with food and because it’s so crucial to our health and the environment, people should be very concerned about how it’s produced. But we don’t always get it right. Next time you’re at the grocery store, consider these 10 modern myths about the most ancient occupation. Read more…
Millions of people around the world will soon celebrate Earth Day, but for hundreds of New England’s dairy farmers, every day is Earth Day.
We’re talking about farmers like the Erb family. The Erbs own and operate Springvale Farms and Landaff Creamery in Landaff. This was one of three pilot farms that assisted the Manomet Center for Conservation Sciences in creating an on-farm sustainability assessment tool, called the Vital Capital Index for Dairy Agriculture. This tool allows farms to measure what matters and establish a baseline of sustainability on farms. Read more…
On July 29, 2016, President Obama signed into law an Act amending the Agricultural Marketing at of 1946 which provides for a national bioengineered food di
Click on the link below to see the letter.
When you think of water, what comes to mind? Is it a cool swig after a hard workout? Is it your beach vacation from last year? Or is it whether or not enough water will fall from the sky to grow your food?
March 22 is World Water Day, and it’s an opportunity to reflect on the importance of water. This year’s theme is “better water, better jobs.” How does water impact agriculture, which employs nearly 1 billion people around the world? Let’s take a look.
Although nearly 70 percent of the Earth is covered in water, only 2.5 percent of that water is fresh. To complicate things, only 1 percent of that fresh water is easily accessible. To sum it up, only 0.025 percent of the planet’s water is available for human use.
Agriculture uses a lot of water, accounting for almost 70 percent of all withdrawals and up to 95 percent in developing countries where there may be fewer technologies to make water use efficient. While you only need to drink about a gallon of water per day, it takes 528 to 1,320 gallons of water to grow the food you eat in a single day. Think about that.
Water is important in maintaining food security, which is defined as “regular access of people to enough high-quality food to leave active, healthy lives.” Lack of water, or too much water, can contribute to famine and undernourishment, especially where people depend on local agriculture for their livelihood. Using water efficiently is critical.
Irrigation is an important technology to help maximize the efficiency of water use in agriculture. The highest yields that can be obtained from irrigation are more than double the best yields from rain-fed agriculture. For instance, drip irrigation involves distributing water at very low rates from a system of plastic pipes with outlets called emitters or drippers. The water is released so that the only part of the soil that receives moisture is where the root grows.
Read the entire article and learn more about agricultural innovation here.
At first blush, it sounds like a good idea: require the labeling of genetically engineered foods so that consumers can make informed choices about what they eat. Yet such a law, proposed by U.S. Sen. Richard Blumenthal and other senators, simply caters to unjustified worries and makes no sense scientifically.
Genetically modified food isn’t new. Since farming began, humans have been breeding food — in other words, changing the genetics — for beneficial traits and better crops. The practice has moved from the field to the lab, as scientists can now transplant genes from species to species.
The laboratory angle worries some people, and in recent years about 2,000 studies have been done on genetically modified foods to uncover any problem. The result? According to the American Medical Association, the World Health Organization, the National Academies of Science and several other groups, so-called GMO food — made with genetically modified organisms — is safe.
As the European Commission put it, engineering crops genetically is “no more risky than conventional plant-breeding techniques.”
Despite the failure of research to come up with hazards, what’s wrong with better informing consumers by labeling genetically engineered food? Several things.
Such a move doesn’t inform consumers so much as it caters to misconceptions, and government shouldn’t be about that. Labels may limit consumer choice: Despite the lack of proof that such crops endanger anyone, retailers may choose not to stock certain foods. And mostly, politics shouldn’t trump science.
Perhaps the oddest aspect of the genetically engineered label debate is that the labels already exist, in a sense.
The majority of food found in the supermarket, especially processed food, contains some genetically engineered component. Non-engineered items routinely carry the label “USDA Organic.”
Lack of such a designation almost always indicates some genetic engineering, so those who are worried about a potential hazard need only look for the label. No new law is necessary.
A Pew Research Center study on science literacy, undertaken in cooperation with the American Association for the Advancement of Science (AAAS), and released on January 29, contains a blockbuster: In sharp contrast to public skepticism about GMOs, 89% of scientists believe genetically modified foods are safe.
That overwhelming consensus exceeds the percentage of scientists, 88%, who believe global warming is the result of human activity. However, the public appears far more suspicious of scientific claims about GMO safety than they do about the consensus on climate change.
Some 57 percent of Americans say GM foods are unsafe and a startling 67% do not trust scientists, believing they don’t understand the science behind GMOs. Scientists blame poor reporting by mainstream scientists for the trust and literacy gaps.
The survey also contrasts sharply with a statement published earlier this week in a marginal pay-for-play European journal by a group of anti-GMO scientists and activists, including Michael Hansen of the Center for Food Safety, and philosopher Vandana Shiva, claiming, “no scientific consensus on GMO safety.”
A huge literacy gap between scientists and the public on biotechnology is one of the many disturbing nuggets that emerged from the Pew Research Center survey, which was conducted in cooperation with the AAAS, the world’s largest independent general scientific society. The full study, released on January 29, is available here.
The eye opening take-away: The American population in general borders on scientific illiteracy. The gap between what scientists believe, grounded on empirical evidence, often sharply differs from what the general public thinks is true. The differences are sharpest over biomedical research, including GMOs.
- 88% of AAAS scientists think eating GM food is safe, while only 37% of the public believes that’s true—a 51-percentage point gap
- 68% of scientists say it is safe to eat food grown with pesticides, compared with 28% of citizens—a 40% gap.
- A 42-percentage point gap over the issue of using animals in research—89% of scientists favor it, while only 47% of the public backs the idea.
by Christine Stuart
Less than 24 hours after the Senate approved a bill banning genetically modified grass seed, the House found bipartisan agreement to kill it.
The bill was a top priority for outgoing Senate President Donald Williams. But House Speaker Brendan Sharkey was not sold on the idea or consulted about the bill.
In a show of bipartisanship, Democrats and Republicans worked Thursday to defeat it by a 103-37 vote.
Following the vote, Sharkey said Williams never had a conversation with him about the legislation.
“I’ve never, ever been consulted about this bill by anyone in the Senate,” Sharkey said. “And the advocates wanted a vote on the bill, so I thought it was important to have vote and avoid the distraction that was going to inevitably occur if we kept it on our calendar.”
He said the same thing happened last year with the GMO labeling bill, which bounced back and forth between chambers before finally winning the approval of all the stakeholders.
Sharkey said he voted against the GMO grass bill because he believes there should have been a public hearing.
“It’s too important to take up and do without getting input from all those stakeholders,” Sharkey said.
Genetically modified grass isn’t on the market yet, but supporters worry about what will happen if it gets out there. Proponents of the legislation say the genetically modified grass would increase the use of glyphosate or other herbicides because it would be resistant to those herbicides.
There’s also the threat of the seed spreading and cross-pollinating with other grass species and spreading individual genes from one species to another. This could lead to an artificially modified gene spreading into the broader gene pool, with untold consequences, Williams explained Wednesday during the Senate debate.
However, opponents of the legislation say it sends a bad message to business and scientists.
“We have a bill before us that says if some business out there is even thinking — thinking — about making such a thing, don’t bother cause you ain’t gonna sell it in Connecticut,” House Minority Leader Lawrence Cafero, R-Norwalk, said.
Cafero thought the concept was absurd.
“It doesn’t even exist and we’re going to ban it,” Cafero said. “Put down your beakers, put down your microscopes . . . save your time, change professions, ‘cause you ain’t doing it in Connecticut. Are you kidding me? Are you kidding me?”
A number of lawmakers, even those who supported the bill, said they were insulted the bill wasn’t raised for a public hearing.
“I don’t know anything about the substance to feel comfortable voting on this,” Rep. Michael D’Agostino, D-Hamden, said.
Rep. Mary Mushinsky, D-Wallingford, said she was concerned about how the bill came to the Environment Committee, but she worries the product will be sold next year. She said she believes it could be dangerous to the environment.
“This is our one chance to make this product go away before it arrives in the state,” Mushinsky said.
Lance Latham, a spokesman for Scotts MiracleGro, which is developing a genetically engineered grass seed, said Wednesday that it won’t be on the market for another “few years.”
“They’re welcome to visit our research facilities in Ohio, talk with our scientists and see firsthand why we believe our enhanced grass seed can one day bring about significant environmental benefits,” Latham said. “They’re also welcome to visit any of our facilities in Connecticut and meet with our 260 employees who live and work in the state.”
Despite the vote in the House, Williams said he was proud of what the Senate accomplished.
“Senate Democrats — joined by three Republicans — made history by taking a stand against the chemical companies and special interests which are poised to dump tens of thousands of gallons of pesticides on lawns across Connecticut,” Williams said.
Senate Majority Leader Martin M. Looney called the vote a disappointment.
“The House vote today is disappointing. Despite the fact that research has extensively documented the adverse impact of poisonous chemicals on human health and the environment, all too often government ignores the precautionary principle and takes action only after harm occurs,” Looney said.
In a statement, Senate Democrats said some of those who opposed the ban complained about the process, but failed to acknowledge that the initiative was discussed at two public hearings and that dozens of experts and citizens weighed-in. Organizations such as the Sierra Club and the CT League of Conservation Voters joined regular citizens in supporting the proposal.