Saturday, December 10, 2016

Brave New World


genomemag |  Imagine if doctors could correct a cataract, for instance, not by using a scalpel or laser to perform surgery, but rather by sending off miniature surgical tools to reach right in and fix the diseased gene that was responsible. It might surprise you to learn that scientists have already shown that this sort of thing is doable today — not in humans perhaps, but in much tinier and fuzzier mice in the lab. The procedure doesn’t work perfectly every time (which partly explains why no one has tried it in a person just yet), but when it does, the animals grow healthy and disease-free.

Scientists in China successfully cured 24 mice of their eye condition, which was produced by a single, mutant copy of one gene. That demonstration, reported in the scientific literature two years ago, was billed as the first to show that it’s possible to correct a genetic disease using a genome editing tool, which scientists call CRISPR-Cas9. Although in mice, the findings offered the first proof of principle that scientists and doctors might one day have sufficient skill and precision to edit single-gene disorders out of human genomes in much the same way.

Jinsong Li, one of the leaders of the study from the Chinese Academy of Sciences, said then that he believes it is “absolutely possible to use CRISPR to cure genetic disease in the near future.” As further evidence in support of Li’s conclusion, his paper came out alongside another by researchers in the Netherlands. They had used CRISPR to correct a gene that causes cystic fibrosis in adult stem cells derived from patients with the single-gene disorder.