<qa>  What is the preferred binding site for benzoapyrene diolAberrant methylation is an important event in the transcriptional silencing of candidate tumor suppressor genes in smoking associated malignancies. Furthermore, it is known that methylated CpG islands are the preferred binding site for benzoapyrene diol epoxide and other carcinogens found in tobacco smoke. Binding of these compounds is known to cause DNA adducts and transversion mutations that are often observed in the aerodigestive tumors of smokers. New evidence suggests that specific DNA methylation events are directly linked to tobacco use. The ability to detect such molecular markers during screening of high risk groups would represent a significant advance in cancer screening and early detection. Our group has evaluated specimens to epigenetically profile CpG island hypermethylation in. head and neck squamous cell carcinoma HNSCC tumor samples using a technique known as methylation specific restriction enzyme microarray analysis. This method will be used in this trial to detect alterations in global DNA methylation patterns in subjects who smoke compared to those who dont. 