Despite the identification of one large genomic deletion in BRCA1, our results support the previous conclusions that the genomic rearrangements in BRCA1 and BRCA2 are not a major cause for increased breast cancer susceptibility in Finland, and that the previously reported Finnish founder mutations represent the majority of BRCA1 and BRCA2 positive families [1,2,7-9,27]. This evidence concerns the gene BRCA1 and breast carcinoma.