Based on case-control comparisons, the MCPH1 c.904_916del carriers have a comparable breast cancer risk to that observed for the Finnish PALB2 c.1592delT carriers, evaluated by using both unselected breast cancer (3.3-fold risk for MCPH1 and 3.9-fold risk for PALB2) and familial breast cancer cohort (8.3-fold risk for MCPH1 and 11.3-fold risk for PALB2) [3], the risk being at least moderate and potentially high. Here, MCPH1 is linked to breast carcinoma.