A group of Chinese scientists from Chengdu have just become the first to use CRISPR-Cas9 gene-editing technology on an actual full-grown human being.
Simply put, CRISPR-Cas9 is a technology which allows geneticists and medical researchers to edit parts of the genome (genes present in a cell) by modifying sections of the DNA sequence in hopes of improving the cells’ ability to combat diseases.
The procedure is done either in two or three steps.
First an RNA sequence serves as a guide to the CRISPR construct to a targeted section of the organism’s DNA. Next, the Cas9 enzyme slices that segment of DNA out. The optional third step allows for a replacement DNA sequence to be inserted in the removed part.
The Chinese trial, conducted on October 28 at the West China Hospital in Chengdu, carried out only the first two steps of the CRISPR-Cas9 procedure, according to Popular Mechanics.
The team of scientists from Sichuan University in Chengdu reportedly injected genetically-edited cells to a person, a feat never done anywhere else.
Approved back in July, the trial involved using the patient’s own immune system cells which were modified using CRISPR-Cas9 to make them more effective at combating cancer cells before injecting them back into the patient. Nine more patients in the trial are scheduled to receive injections of edited cells as well.
United States medical scientists have proposed a similar trial as an experimental treatment for cancer patients in June but is slated to push through in early 2017 as it awaits approval from the Food and Drug Administration (FDA). In the upcoming U.S. trial, immune system cells from 18 patients are scheduled to be modified to include a protein that helps target cancer cells in addition to removing the immune system-damaging protein called PD-1.
The primary objective of both group of scientists is to test the safety of CRISPR treatments rather than cure the subjects from cancer.
If the trials succeed, it would mean a huge medical breakthrough and the technique could be scaled up potentially replace current treatments that use antibodies to neutralize PD-1.
It is worth noting that since the technology is new, such early steps should be observed with caution. A different group of Chinese scientists also ran CRISPR experiments on human embryos last year with unsatisfying results. The trial produced genetic mutations to at least two-thirds of the embryos, leaving just a fraction of the remaining embryos with the replacement genes.