Discovering A New Mechanism For Sex Control In Zebrafish

Temasek Life Sciences Laboratory, Hokkaido University and Ehime University are pleased to announce that their researchers have discovered that the reduction of gonadal stem cells will yield more male zebrafish. The article reporting this finding has been published online in Stem Cell Reports.

These results indicate that a certain number of these specialized gonadal stem cells (primordial germ cells or PGCs) is required for ovary formation. Reduced PGC numbers result in more males, as some of the females are forced to change their sex permanently without affecting their fertility, indicating that PGC count plays a regulatory role during sexual differentiation in zebrafish. The findings suggest that a stem cell counting mechanism in the zebrafish gonad is important for determining sexual development, which provides new insight in vertebrate germline biology.

The sex ratio of cultured stocks is an important aspect of aquaculture, as there are distinct differences (e.g. size, colour, maturation, etc.) between the two sexes in several fish species. This discovery may provide potential tools for improved sex control of fishes in farms in the future.