Scientists call for caution in gene editing

Controversial technology 'should not be used on human embryos until issues resolved'

WASHINGTON • Scientists and ethicists at an international meeting in Washington said it would be "irresponsible" to use gene editing technology in human embryos for therapeutic purposes, such as to correct genetic diseases, until safety and efficacy issues are resolved.

The statement on Thursday, issued after three days of meetings, comes as debate grows over the use of powerful new gene editing tools in human eggs, sperm and embryos, which are called germline cells. Such tools have the power to change the DNA of unborn babies.

But organisers of the International Summit on Human Gene Editing, held to discuss such new gene-editing techniques, said editing genes was permissible for research so long as the modified cells would not establish a pregnancy.

The group's guidance follows calls for various bans on use of the technology called CRISPR-Cas9, which has quickly become the preferred method of gene editing in labs. CRISPR-Cas9 works as a type of molecular scissors that can selectively trim away unwanted parts of the genome and replace them with new stretches of DNA.

Advocates say it will herald the day that scientists are able to prevent hereditary diseases sooner. Opponents worry about unknown effects on future generations and the temptation by future parents to pay for genetic enhancements.

"It would be irresponsible to proceed with any clinical use of germline editing unless and until the relevant safety and efficacy issues have been resolved... and there is broad societal consensus about the appropriateness of the proposed application," said the statement from the group, which included scientists from 20 nations including Britain, China and the United States.

It warned that if genetic alterations were introduced into the human population, they "would be difficult to remove and would not remain within any single community or country". They also raised the possibility that "permanent genetic 'enhancements' to subsets of the population could exacerbate social inequities or be used coercively".

But the group endorsed research on the use of gene editing in non-reproductive or "somatic" cells towards the development of treatments, such as for sickle cell disease or HIV.

The meeting was convened by the National Academies of Medicine and Sciences, the Chinese Academy of Sciences, and the Royal Society of the United Kingdom.

Dr Jacob Corn, scientific director of the Innovative Genomics Initiative, said the group's statement was "very responsible". The statement "is also forward-thinking enough to recognise that we may eventually be able to tackle such issues, though it may take a while".

Dr Debra Matthews, an ethicist and expert on stem cell science at the Johns Hopkins School of Medicine, said the committee's decision to draw the line at germline editing at reproduction was curious, especially in the light of past controversies about embryonic stem cell research.

"I can understand why they did that but I disagree," she said.


A version of this article appeared in the print edition of The Straits Times on December 05, 2015, with the headline 'Scientists call for caution in gene editing'. Print Edition | Subscribe