BRCA1 and hypoparathyroidism-retardation-dysmorphism syndrome: However, recent data based on genomic signatures, i.e., mutations in the BRCA1 or BRCA2 genes or methylation of the BRCA1 or RAD51C promoters, lead to homologous recombination deficiency (HRD) and highlight the existence of HGSOC molecular subgroups (Goundiam et al., 2015, Wang et al., 2017).