转基因作物可以抵抗虫害和除草剂，产量也更高。世界各地的科学家对食用转基因作物制成的食品是否安全进行了密集的研究。

他们的答案是肯定的。

但是某些国家，其中很多在欧洲，都禁止农民种植这些作物，并且对进口转基因生物（genetically modified organisms）制成的食品施加限制。

人们在这方面获得了大量的证据，同时一些诺贝尔奖得主也发出呼吁，强调在全世界数百万人挨饿之际，提高农业产量是当务之急。但有关国家仍然坚持己见。

美国国家科学、工程和医学院（National Academies of Sciences, Engineering, and Medicine）的一份报告表示，未发现人口健康受到的负面影响可归咎于基因工程，同时也未发现造成环境问题的证据，

法国、英国及其他十几个国家的科学家协会都得出同样的结论。欧洲委员会（European Commission）也得到这样的结论。通过审议四分之一世纪的研究结果， 欧洲委员会的结论是，与常规品种相比，生物技术并不具有更高的风险。

相关规定各不相同

美国种植的生物技术作物在全世界处于领先地位，其中大多数是大豆、玉米和棉花。在欧洲，很多国家进口转基因品种用于饲养动物，但是禁止本国农民为种植人类食用的生物工程作物。欧洲食品安全当局（European Food Safety Authority）允许种植某些转基因大豆，但不包括所有的品种。另外，食品标签须注明包含转基因生物。美国也有同样的标注要求。

据美国国会研究服务部（Congressional Research Service）说，中国和其他一些国家实施进口限制，但欧洲联盟（European Union）的规定属最严厉和繁琐之列。

据国际农业生物技术应用服务组织（International Service for the Acquisition of Agri-Biotech Applications）提供的资料， 2017年全世界有67个国家种植生物技术作物，其中24个国家的种植面积达创纪录的1.9亿公顷。

8月27日至29日，非洲生物技术企业，投资人和政府部长在南非德班（Durban）举行首届生物非洲大会（BIO Africa Convention），促进使用作物抗旱生物技术和新疫苗。

南非科学技术部长马莫罗科·库巴伊-恩古巴内(Mmamoloko Kubayi-Ngubane)将主持会议开幕式。南非是非洲种植转基因作物的少数几个国家之一。

有人批评欧洲以严厉的规定掩盖为保护欧洲大陆近1,100万农民不受竞争伤害进行的努力。咨询企业全球农业趋势（GlobalAgriTrends）创始人布雷特·斯图尔特（Brett Stuart）说，“规模很小的农场无力进行生产价格的竞争。如果希望保留这些小农生产，就必须在周围建造保护墙。”

从杂交育种到基因编辑系统

长期以来生物学家通过杂交技术生产优良作物，最初在上世纪80年代采取基因工程，集合各种植物的特质抵抗虫害和除草剂。

现在，推动医药取得突破性进展的科学同样有可能促进农业革新。这种技术被称为基因编辑系统（CRISPR），全称是规律成簇的间隔短回文重复序列（Clustered Regularly Interspaced Short Palindromic Repeats），可以使科学家改变作物本身的基因，但不必借助另一种不同作物的基因。美国农业部（U.S. Department of Agriculture）表示，对待基因编辑系统作物的方式与传统作物没有差别。

但是，欧洲联盟高级法院7月25日裁定，改良基因作物受制于和从另一有机生物提取基因的作物一样的严格规定。北卡罗莱纳州立大学（North Carolina State University）食品科学家和基因编辑系统的开拓性人物鲁道夫·巴兰古（Rodolphe Barrangou）说，反转基因生物团体和公众对大农业公司的不信任助长了人们对科学的质疑，这一点在欧洲已经根深蒂固。

巴兰古说，目前全世界人口为76亿，2025年将达到100亿。“今后面临的挑战是，以较少的可耕土地和水源供养这些人口。我们需要最好的科学和技术达到目的。”

本文原版发表于7月12日。

Tools of modern science help farmers feed a hungry world

Scientists around the world have closely examined whether food grown from plants that are genetically modified to resist pests and herbicides and yield more abundant crops are safe to eat.

Their answer is yes.

But some countries, including many in Europe, ban farmers from planting these crops and restrict imports of food made with biotechnology, or genetically modified organisms (GMOs).

They do so despite the mountain of evidence and urgings from Nobel laureates that in a world where millions go hungry, it’s imperative to boost farm production.

A National Academies of Sciences, Engineering, and Medicine review concluded that “no adverse health effects attributed to genetic engineering have been documented in the human population,” nor evidence found of environmental problems.

Scientific societies in France, the United Kingdom and dozens of other countries have reached the same conclusion. So has the European Commission. Reviewing a quarter-century of studies, it concluded that biotechnology was no more risky than conventional breeding.

Varying rules

The United States leads the world in growing biotech crops — mostly soybeans, corn and cotton. In Europe, many countries import modified feed for animals but bar farmers from growing bioengineered crops for humans. The European Food Safety Authority has allowed some modified soybeans, but not all varieties. Processed foods must disclose GMO ingredients on labels. (The United States also is instituting a labeling requirement.)

China and some other countries impose restrictions, but the European Union’s rules are among “the most stringent and onerous,” the Congressional Research Service says.

Sixty-seven countries used biotech crops and 24 countries grew them on a record 190 million hectares in 2017, according to the International Service for the Acquisition of Agri-Biotech Applications.

African biotech businesses, investors and government ministers are meeting in Durban, South Africa, August 27–29 at the inaugural BIO Africa Convention to advance the use of biotechnology for both drought-resistant crops and new vaccines.

South African Minister of Science and Technology Mmamoloko Kubayi-Ngubane will open the conference. South Africa is one of the few countries on the continent that grows genetically modified crops.

The European Union’s critics say its tough rules mask an effort to protect the almost 11 million farmers on the continent from competition. “Very small farms cannot compete on production costs. If you want to keep those small farmers’ farming, you’ve got to build walls around yourself,” says Brett Stuart, founder of GlobalAgriTrends, a consulting business.

From cross-breeding to CRISPR

Biologists have long cross-bred plants to produce better crops. They began using genetic engineering in the 1980s to introduce traits from different plants to resist pests and herbicides.

Now the same scientific advances promising breakthrough medicines could revolutionize agriculture. The technique called CRISPR (an acronym for Clustered Regularly Interspaced Short Palindromic Repeats) allows scientists to alter a plant’s own genes without borrowing from a different plant. The U.S. Department of Agriculture says it will treat CRISPR plants no differently than those bred traditionally.

But the European Union’s top court ruled July 25 that gene-edited crops are subject to the same strict rules as older, genetically modified plants that borrowed DNA from another organism. Rodolphe Barrangou, a North Carolina State University food scientist and CRISPR pioneer, says public skepticism of science fueled by anti-GMO groups and distrust of “Big Ag” companies are deep-seated in Europe.

The world population, now 7.6 billion, will approach 10 billion by 2050, says Barrangou. “The challenge that lies ahead is feeding them with less arable land and less water. We need the best science and technology possible to do that.”

A version of this story was previously published on July 12.