Valine 1532 of human BRC repeat 4 plays an important role in the interaction between BRCA2 and RAD51

► Analysis of the functions of BRC repeat 4 of BRCA2 between mammalian species. ► The V1532I substitution in human BRC4 strengthens its interaction with RAD51. ► V1532I interferes with RAD51 oligomerization more than wild-type BRC4. ► The V1532F mutant in breast cancer patients reduces interaction with RAD51.