BRCA1 and breast carcinoma: Given the strong contributory history of inadequate SFR to epithelial cancer development and the fact that it is, thus far, the only apparent haploinsufficient BRCA1 DNA repair abnormality, we speculate that SFR haploinsufficiency serves as an early and persistent contributor to the long process that gives rise to BRCA1 breast cancer (Fig. 6e).