Recurrent hydatidiform moles

Hydatidiform mole (HYDM) is an abnormal human pregnancy composed of hyperproliferative trophoblast occurring in approximately 1 in every 1500 pregnancies in Europe and North America. This incidence is higher in other areas in the world. Recurrent hydatidiform mole (RHM), the familial cases of the disease, is an autosomal recessive disorder in which molar tissues are diploid and have a biparental contribution to their genome. The molar tissues show abnormal epigenetic marking of maternal imprinted genes. Affected women have biallelic mutations in the NLRP7 gene (NALP7), a gene thought to be involved in inflammatory and apoptotic pathways.