BREAST-CANCER AND CYPIA1, GSTM1, AND GSTT1 POLYMORPHISMS - EVIDENCE OF A LACK OF ASSOCIATION IN CAUCASIANS AND AFRICAN-AMERICANS

Genetically based differences in carcinogen metabolism have been relat ed to polymorphisms of the cytochrome P450IA1 gene (CYPIA1) and the nu ll genotypes of glutathione S-transferase classes mu and theta (GSTM1 and GSTT1), By PCR Ne examined the genotypes of CYPIA1, GSTM1, and GST T1 in relation to breast cancer risk in Caucasian and African-American women, The study included 164 Caucasian and 59 African-American women with primary invasive breast cancer and age-matched female controls. Enzyme polymorphisms included in this study were the null deletions of GSTM1 and GSTT1 and the m1 (MspI), m2 (codon 462: isoleucine-->valine ), m3 (MspI-AA), and m4 (codon 461: threonine-->asparagine) polymorphi sms of CYPIA1. Contrary to previous reports by other investigators, no ne of the enzyme genotypes, individually or combined, appear to associ ate with an increased risk for breast cancer in Caucasian or African-A merican women. We also report that the recently described m4 allele oc curs at a Lower frequency in African-Americans than Caucasians and is not linked with breast cancer in either race. Thus, it is unlikely tha t polymorphisms of GSTM1, GSTT1, or CYPIA1 represent susceptibility fa ctors for breast cancer in Caucasians or African-Americans.