RAD51C and breast cancer: Consistent with previous findings for RAD51C LoF carriers, rare MS variants were significantly enriched in the ER-negative BC subgroup (OR 1.70, 95% CI 1.00–2.74, p = 0.04), with a similar but non-significant trend in TN BC cases (OR 1.60, 95% CI 0.83–2.85, p = 0.11).