THE 12-BASE-PAIR DUPLICATION INSERTION ALTERATION COULD BE A REGULATORY MUTATION/

A wide array of mutations now numbering more than 200 have been identi fied in the BRCA1 gene, one of the two breast cancer susceptibility ge nes identified so far. in addition, there have been several variants d escribed but it is not known if they really represent functionally sig nificant mutations of the BRCA1 gene. We report evidence to show that the duplication/insertion of 12 base pairs in intron 20 could have a r eal effect on expression of the BRCA1 gene, although it was also prese nt in 1% of our control population.