We have previously reported that xeroderma pigmentosum Group D (XPD), apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1), mut Y DNA glycosylase [11] and murine double minute 2 homolog [12] polymorphisms increase HNSCC risk in the North-East Indian population, and expression of the breast cancer susceptibility 1 protein is downregulated in peripheral blood lymphocytes (PBLs) of HNSCC patients of the region, with potential for acting as an independent, blood-based biomarker of HNSCC [13]. This evidence concerns the gene APEX1 and xeroderma pigmentosum-Cockayne syndrome complex.