BRCA2 and lung cancer: When the two genes were pooled together, BRCA1 was not associated with increased lung cancer risk with RR of 0.66 (95% CI, 0.41–1.05), BRCA2 had an RR of 0.76 (95% CI, 0.48–1.19), and the overall RR is 0.96 (95% CI, 0.66–1.40, Figure 2).