Image of the Day: Lefties

Snails with a gene knocked out by CRISPR grow with their shells coiling in the opposite direction.

Chia-Yi Hou
May 15, 2019
A CRISPR-created snail with the Lsdia1 gene knocked out (left) shows left-handed or sinistral coiling. The wildtype snail with a right-handed or dextrally coiled shell is on the right.

Scientists report that knocking out the Lsdia1 gene using CRISPR in the freshwater snail Lymnaea stagnalis reverses the direction of shell coiling. The snail shell typically coils in the right-handed or dextral direction, but the snails with the Lsdia1 gene knocked out coil in a left-handed or sinistral direction.

M. Abe, R. Kuroda, “The development of CRISPR for a mollusc establishes the formin Lsdia1 as the long-sought gene for snail dextral/sinistral coiling,” Development, doi:10.1242/dev.175976, 2019.