Debating the ethics of human gene editing

Rewriting your DNA is getting closer to reality. A revolutionary technology is opening new frontiers for genetic engineering a promise of cures for intractable diseases along with anxiety about designer babies.

It’s a question that gained urgency after Chinese researchers made the first attempt at editing genes in human embryos, a laboratory experiment that didn’t work well but did raise the prospect of one day altering human heredity passing modified DNA to future generations.

“This is a technology that could have profound implications for permanent alteration of the human genome,” molecular biologist Jennifer Doudna of the University of California, Berkeley, wrote in the journal Nature on the eve of the international summit.

Doudna co-invented the most-used gene-editing tool, and her calls for scientists, policymakers and the public to determine the right balance in how it’s eventually used led to this week’s gathering.

At issue are tools to edit precisely genes inside living cells, finding specific sections of DNA to slice and repair or replace much like a biological version of cut-and-paste software. There are a few methods but one with the wonky name CRISPR-Cas9 is so fast, cheap and simple for biologists to use that research is booming.