There’s been a breakthrough in Science which may lead to delivering a baby free of certain genetic defects.
Chinese researchers used a genome editing technique which is called CRISPR. It was used to rid normal embryos of hereditary diseases that cause blood disorders and other ailments, according to New Scientist.
Experts who have reviewed the project told the publication that, it looks promising even though it involved just six embryos.Robin Lovell-Badge, a human genome expert at the Francis Crick Institute in London, told New Scientist: “It is encouraging.”
The acronym CRISPR stands for “Clustered Regularly-Interspaced Short Palindromic Repeats,”. The technique is a method of disabling genes by introducing small mutations that disrupt the code of a DNA sequence.
Before this experiment, studies involving the CRISPR technique have focused on its use in abnormal embryos which could never fully develop and for bioethics reasons, it was not previously used on healthy, or normal embryos.
The experiment has successfully repaired just below 10 percent of genetic mutations, a rate which is too low to be practical, but high enough to be encouraging.
According to the report, the Chinese team working at the Third Affiliated Hospital of Guangzhou Medical University first worked with abnormal embryos, with little success. However, when they tried to repair mutations in normal embryos from immature eggs donated by people undergoing IVF, they had a breakthrough.
The eggs had presented less of a bioethical dilemma, as they are usually discarded by IVF clinics. However healthy children have been born from such eggs. The team fertilized each egg by injecting sperm from 1 of 2 men with a hereditary disease, then used the CRISPR technique on the single-cell embryos before they started dividing.
In the first case, the technique zapped a mutation that causes favism, which is a condition in which consumption of fava beans causes the destruction of red blood cells.
In another case, it fixed a mutation that causes the blood disease beta-thalassemia, which is a group of inherited blood disorders that affect about 1 in every 100,000 people.
Another expert told New Scientist the results were indeed compelling. Fredrik Lanner, of the Karolinska Institute in Sweden, told the publication. “It does look more promising than previous papers,”
This breakthrough could lead to wider experimentation with using CRISPR to edit the genomes of normal human embryos. Experts, however, cautioned that technology is far from the point where it could be safely used for editing embryos.