An association study of ~800 BRCA1/2 mutation-negative familial breast cancer cases and over 1,000 controls from Germany found some evidence that the PPARGC1A Thr612Met polymorphism might be a risk factor for familial breast cancer (OR = 1.35, 95% CI 1.00-1.81, P = 0.049), high-risk familial breast cancer (OR = 1.51, 95% CI 1.08-2.12, P = 0.017) and bilateral familial breast cancer (OR = 2.30, 95% CI 1.24-4.28, P = 0.009) [47]. Here, PPARGC1A is linked to breast cancer.