Oct 30, 2017
Origin: ASRM Press Release
HIGHLIGHTS FROM THE AMERICAN SOCIETY FOR REPRODUCTIVE MEDICINE’S
2017 SCIENTIFIC CONGRESS & EXPO
San Antonio, TX– Today at the Scientific Congress and Expo of the American Society for Reproductive Medicine, Dr. Dieter Egli and his team from Columbia University announced that they had used CRISPR/CAS9 to edit mutations in haploid human embryonic stem cells.
Treating haploid embryonic stem cells from a line created from the parthenogenetically-activated egg of a donor with a heritable gene mutation, the researchers corrected the mutation in 14.6% of cell lines, maintaining a normal karyotype and an average of 47.5% haploid cells in culture
Haploid stem cells evidencing the mutation of interest – confirmed as a heritable, rather than a new mutation, through genetic sequencing of the stem cells and of fibroblast cells from the egg donor- were concentrated in culture. Guide RNA and a correction template were designed; cells were nucleofected, cultured for two more days, then sorted to extract haploid cells expressing CAS9 tagged with green fluorescent protein (GFP). After culture, 48 clonal cell lines were sequenced; in seven of them (14%) the mutation had been corrected. Two of the corrected lines were further evaluated to confirm the degree to which they remained haploid and chromosomally normal and that there were no off-target effects.
ASRM President Elect Christos Coutifaris, MD, PhD, commented, “This well-designed proof of concept study demonstrates the feasibility of correcting harmful mutations in haploid cells and has implications for correcting gametes. Much research remains to be done and the technique’s safety, as applied to reproductive cells, must be proven, but gene-editing may someday allow carriers of harmful genes to have their own genetic children without passing these pathogenic genes on to them.”