The cumulative risk (95% CI) of breast cancer to age 80 was highest in Chinese-ancestry women followed by Indian-and Malay-ancestry women (Chinese versus Indian versus Malay: 55% (51–60%) versus 49% (44%–53%) versus 40% (36–44%) for BRCA1 (pairwise p-values <0.05), and 42% (38–45%) versus 36% (33%–40%) versus 29% (26–32%) for BRCA2 (pairwise p-values <0.05 except for Chinese versus Indians where p-value was 0.07) (Fig. 1a and b and Table 2). This evidence concerns the gene BRCA1 and breast cancer.