Loss of heterozygosity (LOH) at multiple chromosome regions and genetic and epigenetic alterations of several proto-oncogenes and tumour suppressor genes have been demonstrated in oral carcinomas, including alterations of the TP53, p16, p15, MGMT, E-cadherin genes and RAS (Califano et al, 1996; Partridge et al, 1999; Williams, 2000; Ogi et al, 2002; Viswanathan et al, 2003). Here, MGMT is linked to lip and oral cavity carcinoma.