A relative risk of 1.1 (95% CI 0.5–2.6) was observed for women with 28 or more CAG repeats from a pooled analysis of 188 BRCA1 and BRCA2 mutation carriers [8], whereas a study of 227 BRCA1 and BRCA2 mutation carriers reported shorter mean CAG repeat number in women with breast cancer diagnosed before age 42 years as compared with those diagnosed after this age [9]. Here, BRCA1 is linked to breast cancer.