To do so, we sequenced the complete coding regions for the CHEK2 and p14(ARF) genes and analyzed for p14(ARF) promoter hypermetylations; 3) Evaluate in vitro function of potential Chk2 and p14(ARF) protein translates corresponding to identified mutations in the CHEK2 and p14(ARF) genes; 4) Identify potential TP53, CHEK2 and p14(ARF) mutations to be germline, explore the incidence of different cancers among affected relatives with respect to specific mutations. This evidence concerns the gene CHEK2 and cancer.