The SNPs evaluated in this study were chosen based on previous knowledge of common genetic variation resulting from re-sequence analysis, captured most of the common variation in the five studied genes (i.e. POT1, TEP1, TERF1, TERF2 and TERT), and could be related to breast cancer risk based on the role suggested for telomere biology in this disease (Baykal et al, 2004; Wacholder et al, 2004; Savage et al, 2005). This evidence concerns the gene TERF1 and breast cancer.