While usage of tobacco in any form is associated with higher risk of developing oral cancer, difference in the ability to metabolize these chemical carcinogens forms the basis of interindividual variability to develop cancer apart from the magnitude of exposure to the carcinogen. These chemical carcinogens require activation by Phase I metabolizing enzymes followed by detoxification via conjugation by Phase II enzymes. Polymorphisms in these xenobiotic metabolizing enzymes can lead to an increased risk of developing HNSCC. Hence the objective of the project is to investigate the role of genetic polymorphisms in the risk of developing HNSCC and to calculate the prevalence of these genetic polymorphisms (minor allele frequency) among the participants.