A NOVEL CYP1A1 GENE POLYMORPHISM IN AFRICAN-AMERICANS

A new Msp1 RFLP in the CYP1A1 gene has been found in genomic DNA from African-Americans. The polymorphism results from a single A-T to G-C t ransition in the 3' noncoding region approximately 300 bp upstream fro m the polyadenylation site. This mutation leads to cleavage of the nor mal 2.3 kb MspI restriction fragment into 1.3 and 1.0 kb fragments. Th e heterozygous mutation has been seen in 8 of 47 African-Americans, bu t was not detected in 191 Caucasians or 30 Asians. No linkage was obse rved with either of the two previously described polymorphisms in this gene.