Genetic control of early folliculogenesis in mice.

Perinatally, granulosa cells encase individual oocytes within the ovary to form primordial follicles. The initial stages of folliculogenesis are independent of gonadotropins and involve cell-autonomous and non-cell-autonomous factors. Although still poorly understood at a molecular level, successful follicle formation and initiation of follicle growth must involve genetic networks both in germ and in somatic cells. Mouse models offer useful windows into these essential processes. By investigating phenotypes of mouse lines lacking specific gene products, genetic hierarchies that regulate the initial stages of folliculogenesis are being elucidated. These investigations will provide insight into the regulation of mammalian fertility.