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Gene¹-edited Food Will Arrive Soon, But Will People Eat It?

Foods based on the latest biotechnologies will soon be available in grocery stores around the country.

The first foods from plants or animals that have had their genetic² material, or DNA³, “edited” are expected to appear on the market as early as next year.

Genetically⁴ edited food uses a different technology from “genetically modified,” or GMO, foods, which are already available in many countries including the U.S.

The U.S. National Academy of Sciences says that gene editing is needed to improve food production in order to feed the world’s growing population.

However, governments do not yet know how to oversee⁵ this new tool. It also is unclear whether people will be willing to buy gene-edited foods.

Dan Voytas is with Calyxt Inc., which edited soybean DNA to give it new qualities. “If the consumer sees the benefit, I think they’ll embrace the products and worry less about the technology,” he said.

Researchers are using the technology to make several new kinds of crops. They include high-fiber wheat, mushrooms that keep their color and highly-productive tomatoes. They also are trying to develop corn that resists dry weather conditions and rice that resists pollution.

Some scientists say they hope to use gene-editing to end crop diseases like citrus greening which affects fruits like oranges. However, they first must find the genes⁶ that could help a plant resist the disease.

Fred Gmitter is a geneticist at the University of Florida Citrus Research and Education Center. He said if scientists can make small changes to a plant’s DNA, then “we’d have a way to defeat this disease.”

The difference between gene-edited and GMO

For hundreds of years, farmers have genetically changed crops and animals by breeding them for desired qualities. This selective breeding results in giving up some other qualities. For example, modern tomatoes are much bigger than their wild ancestors, but they are more easily damaged and have different nutrients⁷.

GMOs, or genetically modified organisms, are plants and animals that have had DNA from other kinds of organisms mixed with their own to give the new organism a specific quality. Examples of this are corn or soybeans that have had bacterial⁸ genes added to make them resistant⁹ to insects or plant-killing chemicals.

Scientists around the world say GMOs are safe to eat. But that does not keep some people from not liking¹⁰ them. Some people also worry that GMOs will bring unexpected results as they interact with other living things in the natural world.

Now there are gene-editing tools, with names like CRISPR and TALENs. Scientists hope these methods will permit very exact changes to plant or animal DNA without necessarily adding DNA from another organism. These methods act like scissors that can cut off molecules¹¹ in an organism’s DNA.

Scientists say this process could be less costly¹².

So far, researchers have placed most of their efforts not on adding to DNA but on cutting unwanted parts from genes causing them to “turn off.”

The new soybeans developed by Calyxt have two genes that have been turned off in this way. The genes cause the plant to produce trans fats, forms of fat that have been linked to heart disease.

The company Recombinetics Inc. says it has turned off part of a gene that makes Holstein cows grow horns, making them safer to other cows and farmers.

New rules needed?

The U.S. Agriculture Department says extra rules are not needed for “plants that could otherwise have been developed through traditional breeding.”

The Food and Drug Administration, however, in 2017 proposed new rules for gene-edited animals. It has promised to give its opinion on the subject sometime next year.

At the World Trade Organization this month, the U.S. joined 12 nations including Australia, Canada, Argentina and Brazil. They called for other countries to accept international rules for gene-edited agricultural products.

Companies involved in gene-editing also want to avoid reactions similar to those that met GMO foods when they were introduced years ago. Many people reject them. And the European Union has laws limiting their sale and use.

Jennifer Kuzma is with the Genetic Engineering and Society Center at North Carolina State University. She said it is important to make sure gene-edited products are safe.

But she expects about 20 gene-edited crops will arrive on the U.S. market over the next five years. She also said that scientists are studying crops important to the poorest countries like cassava.

“We think it’s going to really revolutionize the industry,” she said.

I’m Mario Ritter.

Words in This Story

DNA (deoxyribonucleic acid) –n. a substance that carries genetic information in the cells of plants and animals

edit –v. to make changes to something, such as a piece of writing, by by adding or removing parts of it

consumer –n. a person who buys goods and services

benefit –n. a good or helpful result or effect

embrace –v. to accept something readily or gladly

breeding –n. the activity of keeping and caring for animals or plants in order to produce more of a particular kind

selective –adj. involving choosing from among a group of people or things to get the best result

1 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

2 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

3 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

4 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

5 oversee   

vt.监督，管理

参考例句：

• Soldiers oversee the food handouts.士兵们看管着救济食品。
• Use a surveyor or architect to oversee and inspect the different stages of the work.请一位房产检视员或建筑师来监督并检查不同阶段的工作。

6 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

7 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》

8 bacterial   

a.细菌的

参考例句：

• Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。
• Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。

9 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。

10 liking   

n.爱好；嗜好；喜欢

参考例句：

• The word palate also means taste or liking.Palate这个词也有“口味”或“嗜好”的意思。
• I must admit I have no liking for exaggeration.我必须承认我不喜欢夸大其词。

11 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

12 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。