Here, we investigated the contribution of BRCA1, BRCA2 and CHEK2 alterations to MBC predisposition in Italy by analysing a large series of MBC cases, unselected for breast cancer family history and all negative for BRCA1/BRCA2 germ-line mutations.
We wanted to evaluate the significance of CHEK21100delC in predisposition to MBC by assessing its frequency in a population-based material of 114 Finnish MBC patients.
Pathogenic variants in BRCA2 [odds ratio (OR) = 13.9; p = 1.92 × 10<sup>-16</sup>], CHEK2 (OR = 3.7; p = 6.24 × 10<sup>-24</sup>), and PALB2 (OR = 6.6, p = 0.01) were associated with significantly increased risks of MBC.
To extend our knowledge on the role of CHEK2 in susceptibility to male breast cancer we have screened a series of 26 breast cancer cases with male representation for germline sequence variation in the CHEK2 gene.