is a female related gene that plays a role in ovarian development and maintenance of function in mammals. However, little is know about the expression and function of during early embryonic development. We investigated the pattern of hybridizationmRNA was low in the fertilized egg, but increased during development. The level of expression wasafter which levels declined significantly. mRNA was at which point we observed a strong positive signal concentrated in the ventral surface near the concave region of the mouth. The intensity of the signal increased significantly visceral mass and the margin of mantle, and was distributed symmetrically. Thereafter, the signal disappeared until sex differentiation, at which time the signal was only detected in the ovary. Our results suggest that the gene participates in the regulation of ovarian development. Furthermore, given the persistent expression during the early development stages, we hypothesize that this gene plays a role in the development of .