STUDIES ON GLUTATHIONE-S-TRANSFERASE GSTM 1 AND GSTT1 GENOTYPES AND SUSCEPTIBILITY TO LARYNGEAL-CANCER

While cigarette smoking and alcohol consumption have been linked to la ryngeal carcinoma, the role of genetic factors in determining individu al susceptibility is unknown. We describe the role of allelism at glut athione-S-transferase GSTM1, GSTT1,and cytochrome P 450 CYP2D6 loci in determining individual susceptibility to laryngeal squamous cell carc inoma. Methods: Enzyme genotypes were determined using the polymerase chain reaction in 169 patients suffering T1-T4 laryngeal carcinoma and in 145 controls. Results: While the frequency of the heterozygote GST M1 A/B genotype was statistically significantly lower in the cases tha n controls, the frequency of the GSTT1 null genotype was higher in cas es than controls. Conclusion: These initial data suggest that allelism at GST loci mediates susceptibility to squamous cell carcinoma of the larynx. Thus, GSTM1 A/B appears to be associated with a reduced risk while GSTT1 null confers increased risk. The findings are compatible w ith the view that genetic predisposition is important in determining r isk of this cancer.