germline variants in early-onset breast cancer patients from hereditary breast and ovarian cancer families.

, located 470 kb downstream of , encodes for the nuclear PSMC3-interacting protein, which functions as co-activator of steroid hormone-mediated gene expression, and is involved in RAD51 and DMC1-mediated homologous recombination during DNA repair of double-strand breaks. Recently, germline variants in have been identified in hereditary breast and ovarian cancer (HBOC) patients, mainly in cases with early-onset. We screened a cohort of 166 mutation-negative HBOC patients, of which 56 developed early-onset breast cancer before the age of 36 years, for variants.