BRCA1 and breast cancer: To establish our theory, we have used total 69 exome datasets that comprise of 11 non-BRCA1/2 familial breast cancer (BC)27, 19 Esophageal Squamous Cell Carcinoma (ESCC) tumour samples (T) with 19 ESCC matching germline normal (N) samples28, and 20 healthy (control) samples (H)27, 29.