A study dealing with modifying human embryo at the level of the genes has received much warning and words of caution from other researchers.
Scientists from China had allegedly edited human embryo genomes successfully, thereby modifying the DNA like it was never done before – the germline, the sensitive genetic information that is brought to existence when an egg and a sperm merge into each other, itself was altered. What was just a rumour seems to have been confirmed: the scientific paper with the findings is said to have been published in a journal known as Protein & Cell.
Now, before you get all excited about prospective genetically modified human beings to come into existence, know that the researchers did their experiments on abnormal embryos only, and did not even attempt to establish a pregnancy.
The aim of the team, led by Junjiu Huang of Sun Yat-sen University in Guangzhou, was to alter the gene responsible for β-thalassaemia, a blood disorder that can gradually lead to death. They made use of a cutting-edge gene editing tool known as CRISPR. They focused their efforts on a single-celled embryo.
Of the 86 embryos made part of the experiment, only 71 survived after being injected with the new gene waiting for the CRISPR/Cas9 system to act. Of these, 54 were genetically tested. It was then found that only 28 were successfully spliced, and only a proportion of them contained the replacement genetic material.
“If you want to do it in normal embryos, you need to be close to 100%,” Huang says. “That’s why we stopped. We still think it’s too immature.”
As a matter of fact, not all embryos had successfully incorporated the new gene in all of their cells. Many of them had some good copies of the gene with some bad ones as well. Consequently, other researchers have formulated a number of warnings to others.
“I believe this is the first report of CRISPR/Cas9 applied to human pre-implantation embryos and as such the study is a landmark, as well as a cautionary tale,” George Daley, a stem-cell biologist at Harvard Medical School, told Nature. “Their study should be a stern warning to any practitioner who thinks the technology is ready for testing to eradicate disease genes.”
As much as the study sounds exciting, other scientists have warned that science has a long way to go before such tests can be done on embryos for implantation. Yet other researchers are cautioning their colleagues from proceeding in that direction. It is to be noted that the authors themselves are cautious with their results, stating that their technique is far from being ready.
So, hear out world. Designer babies are not to be expected in the near future.