A study in fruit flies suggests that existing approaches to gene drives using CRISPR/Cas9, which aim to spread new genes within a natural population, will be derailed by the development of mutations that give resistance to the drive.

Newly developed approaches that use CRISPR/Cas9 gene editing technology can generate offspring that carry copies of the altered gene on both chromosomes -- a phenomenon called super-Mendelian inheritance that, in theory, should quickly convert an entire population. This process, however, can also create resistant genetic sequences and organisms that cannot be converted.