A genetic pathway for the specification of the vulval cell lineages of Caenorhabditis elegans.

Twenty-three genes have been assigned to particular steps in a genetic pathway for the specification of the vulval cell lineages of the nematode Caenorhabditis elegans. Mutations in most of these genes cause homoeotic transformations in the fates of individual cells, suggesting that these lineages may be specified by a series of decisions that distinguish between alternative cell fates. Fifteen of the genes function in a system involved in the intracellular response to the extracellular signal that induces vulval formation.