UK scientists seek permission to edit genes in human embryos

Scientists in the UK have applied for permission to edit the genes of human embryos in a series of experiments aimed studying the earliest stages of human development.

Only months after an international controversy triggered by Chinese scientists, who claimed they had genetically modified human embryos, Kathy Niakan, a stem cell scientist from London's Francis Crick Institute, had asked the UK government's fertility regulator for a licence to carry out similar experiments.

In a statement about her application, made to the Human Fertilisation and Embryology Authority (HFEA), Niakan said her intention was not to genetically alter embryos for use in human reproduction, but aimed to scientific understand how a healthy human embryo developed.

"This knowledge may improve embryo development after in vitro fertilisation (IVF) and might provide better clinical treatments for infertility," she said in a statement, adding that any donated embryos would be used for research purposes only.

A debate is raging in scientific circles over the potential future use of new genetic technology known as CRISPR-Cas9, which allows researchers to edit virtually any gene, including in human embryos.

Even as technology could allow scientists to find and change or replace genetic defects, critics warn it had the potential to create "designer babies" to order.

Niakan's research, if allowed to go ahead could see the first genetically modified embryos in the UK within months.

Donated by couples with a surplus after IVF treatment, the embryos would be used for basic research only and could not be studied for more than two weeks or implanted into women to achieve a pregnancy.

Though the modified embryos would never become children, the move would concern some who had called for a global moratorium on the genetic manipulation of embryos, even for research purposes.

They fear a backlash could derail less controversial uses of genome editing, which could lead to radical new treatments for disease.

Niakan plans to use the procedure to study the role of genes in the first few days of human fertilisation, when an embryo developed a coating of cells that later formed the placenta.

''The knowledge we acquire will be very important for understanding how a healthy human embryo develops, and this will inform our understanding of the causes of miscarriage. It is not a slippery slope [towards designer babies] because the UK has very tight regulation in this area,'' she told the Guardian.

Thanks to a radical new treatment, a British baby boy has become the first in Europe to be born free from a list of genetic disorders.(See: Pioneering DNA treatment allows IVF baby to be born free from genetic disease).