Distribution of alcohol dehydrogenase (ADH1C) genotypes in subjects with tobacco smoke-associated laryngeal cancer

Abstract

Laryngeal cancer in Poland is characterized by high levels of morbidity and mortality. The main risk factors for the larynx cancer are alcohol drinking and tobacco smoking. In contrary to well established tobacco-related evidence for an increased risk of larynx cancer, alcohol-related mechanisms of carcinogenesis remain unknown. Nevertheless the effect of alcohol is modulated by polymorphisms in genes encoding enzymes for ethanol metabolism. Hence we investigated the ADH1C *1 genotype and allele frequency in a group of 102 larynx cancer patients with heavy alcohol consumption recruited from the Department of Otolaryngology and Laryngological Oncology of the University of Medical Sciences in Poznan. The data were compared with 112 non-cancer age-matched individuals consuming similar amounts of ethanol. Blood samples were used for analysis of restriction fragment length polymorphism. DNA was isolated from the whole blood leucocytes and PCR with specific primers was used to amplify polymorphic region of rs698 in the ADH1C gene. The method was based on allele detection by Sspl restriction enzyme digestion and after the incubation with enzyme, samples run on an electrophoresis. The statistic analysis was performed to calculate Odds Ratio (ORs), 95% confidence intervals (CIs) and significance. Results suggest a slightly increased risk of larynx cancer for individuals who have inherited the ADH1C *1 allele (rs 698), however they did not reach the level of statistic significance.