BRCA1 and breast cancer: Using PCR, PAGE, Sanger sequencing, and statistical analyses, we compared VNTR genotypes in the XRCC5 promoter between healthy individuals and three types of familial breast cancer cases: mutated BRCA1 (BRCA1+), mutated BRCA2 (BRCA2+), and wild-type BRCA1/BRCA2 (BRCAx).