Real-time PCR analysis of the N-acetyltransferase NAT1 allele *3,*4,*10,*11,*14 and *17 polymorphism in squamous cell cancer of head and neck

Although tobacco smoke has been established as a main risk factor in the de velopment of head and neck squamous cell cancer (HNSCC), genetic polymorphi sms of xenobiotic metabolizing enzymes are supposed to modulate an individu al's susceptibility to smoking-related HNSCC. N-acetyltransferase (NAT) 1 g ene is known to be polymorphic and its protein product is implicated in the activation and detoxification of carcinogens, such as aromatic amines, pre sent in tobacco smoke. We developed a rapid and reproducible LightCycler(TM )-assisted real-time polymerase chain reaction (PCR) for NAT1 genotyping, w hich allowed the parallel differentiation of NAT1*3, *4, *10 and *11 allele s and separately of NAT1*14 and *17 alleles within 60 min without the need for further post-PCR processing. In order to investigate the role of the NA T1 gene polymorphism as a risk-modifying factor in HNSCC, we tested for the presence of NAT1*3, *4, *10, *11, *14 and *17 alleles in a case-control st udy of 291 HNSCC patients and 300 healthy controls of Caucasian origin. Our findings suggest that in Caucasians, the risk of HNSCC is not associated w ith NAT1 polymorphism. The overall distribution of NAT1 allele frequencies was not significantly different among cases and controls. The presence of t he fast acetylator NAT1*10 and NAT1*11 alleles did not significantly increa se the risk of HNSCC and no modifying effect of NAT1*10 was observed among smokers. This new approach in NAT1 genotyping substantially increases throu ghput of sample analysis and, therefore, enhances opportunities to study NA T1 as a risk factor in different cancers in large-scale studies.