Genetic and epigenetic analysis of recurrent hydatidiform mole.

Familial biparental hydatidiform mole (FBHM) is a maternal-effect autosomal recessive disorder in which recurrent pregnancy failure with molar degeneration occurs. The phenotype mimics molar pregnancy due to androgenesis, despite the normal genetic makeup of the conceptus. FBHM appears to result from a failure to establish correct maternal epigenetic identity at imprinted loci during oogenesis.