The general theme of this book is to identify genetic variants of xenobiotic metabolizing enzyme genes associated with esophageal and gastric cancer susceptibility in Kashmir Valley. Genetic changes may impart growth advantage to cells by possible alteration in xenobiotic enzymes genes; the pivotal molecular machinery in the cell which controls whether a cell will proliferate, differentiate, become invasive and metastasize. Host metabolic enzymes and other protective proteins are known to protect against deleterious effects of carcinogens. Xenobiotic metabolizing enzymes are an important part...