The world’s first monkeys with genes modified through a DNA engineering method known as Crispr/Cas9 were born in a lab. The scientific breakthrough by Chinese researchers could become a cornerstone for research and prevention of human genetic disorders. Researchers at Nanjing Medical University and Yunnan Key Laboratory of Primate Biomedical Research in Kunming in China have created two genetically modified macaques with targeted mutations using the CRISPR/Cas9 system. “Our study shows that the CRISPR/Cas9 system enables simultaneous disruption of two target genes in one step without producing off-target mutations,” study author Jiahao Sha told the Science Daily.“Considering that many human diseases are caused by genetic abnormalities, targeted genetic modification in monkeys is invaluable for the generation of human disease models.” The researchers introduced single-cell macaque embryos with modified Ribonucleic acids (RNAs) to generate the genome-editing process.
RNA is a ubiquitous family of large biological molecules that perform multiple vital roles in the coding, decoding, regulation, and expression of genes. Using the Crispr method, Chinese scientists were targeting three genes in the experiment – one that regulates metabolism, another that regulates immune cell development and a third that regulates stem cells and sex determination. The birth of the genetically modified monkeys was not an easy process. Scientists had to target the genes in 180 single-cell monkey embryos. Eighty three of those 180 embryos were injected into female macaques, yielded only 10 pregnancies. Only one pregnancy so far led to the birth of a pair with simultaneous mutations in two genes. According to coauthor of the study Wezhi Ji, researchers discovered multiple changes in their target genes at different stages of embryonic development. But the newborn macaques are still too young for researchers to determine if their experiment had an effect on physiology or behavior, though “data from this species should be very useful for curing human disease and improving human health,” says Ji. More