DIDEOXY FINGERPRINTING ASSAY FOR BRCA1 MUTATION ANALYSIS

Since the isolation of BRCA1, the familial breast/ovarian cancer predi sposition gene, much effort has been invested in characterizing the mu tation spectrum. The large size of the gene and the wide distribution of its more than 100 mutations has increased the challenge of this end eavor such that traditional mutation detection techniques are inadequa te. We examined the sensitivity of dideoxy fingerprinting (DDF), which combine a Sanger sequencing reaction with multiple-fragment single-st rand conformation analysis (SSCA), as a mutation detection technique t o screen BRCA1. Here we describe the technique and compare its sensiti vity with that of SSCA in detecting 21 previously described BRCA1 sequ ence variants. All the variants were detected by DDF, but only 17 of 2 1 (81%) were observed by SSCA under standard conditions. Three of four alterations missed by SSCA were base substitutions. As a BRCA1 mutati on detection technique, DDF was more sensitive than SSCA and may prove to be a useful research tool in defining the mutation spectrum within this and other genes. (C) 1997 Wiley-Liss, Inc.(+)