CHEK2 and breast cancer: This is a retrospective cross-sectional study that aims to evaluate the germline profile of P/LP variants in 13 HMP BC genes (BRCA1, BRCA2, PALB2, TP53, CDH1, NF1, PTEN, STK11, CHEK2, ATM, BARD1, RAD51C, and RAD51D) in patients diagnosed with BC in Brazil.