The cytochrome P450 1A1 (CYP1A1) gene may be of critical importance in
determining individual cancer susceptibility to aromatic hydrocarbons
such as those in tobacco smoke. We compared the frequencies of CYP1A1
haplotypes, and complete genotypes, taking into account polymorphisms
at 3 sites, including an African-specific polymorphism. No concordanc
e was observed in Africans or African-Americans between any of the 3 p
olymorphisms, (Msp1 restriction fragment length polymorphism (RFLP)-'M
', exon 7-'E', new RFLP-'A') in contrast to the concordance seen betwe
en the M and E polymorphisms in Caucasians and Asians. We observed an
effect of the E polymorphism on enzyme activity and mRNA induction in
Asians and Caucasians.