在线英语听力室_免费在线英语听力学习网站

Scientists Create New Method for Changing the Genes² of Cockroaches³

Researchers have developed a new method for making changes to the genes of insects called cockroaches.

The scientists said the method could be an important step. They said it could help remove barriers to researching and changing, or editing, genes of all kinds of insects.

The technology used in the new method is called CRISPR/Cas-9. The CRISPR tool makes it possible for scientists to change DNA⁴ by adding or taking away parts of the DNA of living cells. DNA is deoxyribonucleic acid. It is a main substance that carries genetic⁵ information in the cells of living things.

In this file photo, giant Madagascar hissing⁶ cockroaches cling to box before being cremated⁷ at Bangkok hospital on May 23, 2003. (REUTERS/Sukree Sukplang)

CRISPR technology has been used to carry out research and create possible treatments for genetic diseases affecting humans. In 2020, two women were awarded the Nobel Prize in Chemistry for developing the CRISPR/Cas-9 tool.

The method has also been used to target and change genes in animals and insects. Last year, for example, scientists announced they had used the CRISPR/Cas-9 method to block the ability of mosquitos to identify human targets.

The scientists involved in the new study also used the CRISPR/Cas-9 tool. But they developed a new process to improve their research for use with many kinds of insects.

In the past, researchers performing gene¹ editing on insects injected genetically⁸ edited materials directly into developing embryos⁹. But the new method involves injecting the materials into female adults as early eggs are still developing.

The researchers call their new method "direct parental¹⁰" and describe it as "simple and efficient."

Takaaki Daimon of Japan's Kyoto University helped lead the research and was the lead writer of the study. He said in a statement that with the new method, "researchers have been freed from the annoyance¹¹ of egg injections."

Daimon added that the process his team invented simplifies and speeds up gene editing in insects. "We can now edit insect genomes more freely and at will. In principle, this method should work for more than 90 percent of insect species," he said.

The results recently appeared in the publication Cell Reports Methods.

The researchers said cockroaches and many other kinds of insects have unusual reproductive systems. This limits the way the CRISPR editing technology can be used on them. Past attempts that sought to edit the genes of cockroaches failed.

The team said it solved the problem by creating a method that does not require CRISPR materials to be injected into early embryos.

The result successfully created so-called "knockout" cockroaches. The term "knockout" is used by scientists to describe organisms that have had all or part of a gene removed or inactivated¹² by genetic engineering.

In addition, the scientists tested their method on red flour beetles¹³. Those experiments produced results more than 50 percent of the time, the team reported in the study.

The researchers said their results demonstrated that the new method can be used in research involving many kinds of insects. But they noted¹⁴ the process will not work on some kinds of insects that have more complex reproductive systems, such as fruit flies.

The team said their method does not require costly¹⁵ equipment, complex experimental setups or highly skilled laboratory workers. Daimon said, "These problems with (traditional) methods have plagued researchers who wish to perform genome editing on a wide variety of insect species."

Words in This Story

efficient – adj. working well and not wasting time or energy

annoyed – adj. angry or upset

genome – n. the complete set of genetic material of a human, animal, plant, or other living thing

principle – n. a basic idea or rule that explains or controls how something happens or works

plague – v. to cause worry, pain or difficulty to someone or something over a period of time

species – n. a group of animals or plants that are similar and can produce young animals or plants