The 2016 budget prevents the US Food and Drug Administration from spending any of its funds to review or approve gene-editing research that involves the human germline. While this provision was aimed at prohibiting the use of genome-editing tools like CRISPR to create genetically modified babies, Technology Review's Mike Orcutt says it also been interpreted to encompass mitochondrial transfer.
Mitochondrial transfer, also known as mitochondrial replacement or pronuclear transfer, involves the transplantation of a fertilized egg's nucleus into another egg that lacks a nucleus, but contains mitochondria. It's a way for women with mitochondrial diseases to have biological children, while lessening the chance that those kids will inherit the mitochondrial disorder. Such therapies were approved in the UK last year.
According to Orcutt, US regulators say the procedure falls under that gene-editing ban. Oregon Health and Science University's Shoukhrat Mitalipov, who has been working on the approach, tells him that the US needs to better distinguish between gene editing that aims to fix an issue versus to make an enhancement.
Orcutt adds that the ban is "at odds with" a National Academies of Science, Engineering, and Medicine report that found that such therapy was "ethically permissible" if conducted in male embryos and limited to women with mitochondrial diseases.