GENOTYPING METABOLIC POLYMORPHISMS IN A COHORT OF CAUCASIANS AND SINGLE-STRAND CONFORMATION POLYMORPHISM ANALYSIS OF POINT MUTATIONS IN HUMAN HPRT EXONS 7 AND 8

In genetic toxicology, the main fields of applications of the polymera se chain reaction (PCR) with subsequent electrophoretic characterizati on of amplificates include genotyping polymorphisms in the xenobiotic metabolism and mutant analysis. To assess the role of the individual s ets of biotransformation enzymes for the internal dose resulting from xenobiotic exposure, we investigated blood samples from 69 healthy don ors for the occurrence of known genetic polymorphisms in the xenobioti c metabolizing enzymes N-acetylaminotransfrase II (NAT2), glutathione- S-transferase (GST) mu and theta, and several cytochromes P450 (CYP), namely CYP1A1, CYP2E1 and CYP2A6. Using single strand conformation pol ymorphism (SSCP) analysis, five known single base substitutions locate d in the middle portion of 144 bg amplificates comprising exons 7 and 8 of the human hypoxanthine guanine phosphoribosyl transferase (hprt) cDNA, were clearly distinguished from wild type and from each other. B iomagnetic strand separation assigned the slower migrating single stra nd bands to the biotinylated sense strands.