Sánchez-Siles M, Pelegrín-Hernández JP, Hellin-Meseguer D, Guerrero-Sánchez Y, Corno-Caparrós A, Cabezas-Herrera J, Pastor-Quirante F, Fernández-Ruiz JA, Aliaga-Sánchez A, Lucero-Berdugo M, and Camacho-Alonso F
Background: some types of cancer have been associated with the presence of single nucleotide polymorphisms (SNPs) of some genes that encode enzymes: glutathione-S transferase (GST), whose alteration leads to loss of function and a lower capacity to eliminate toxic GSTM1 and GSTT1 null genotypes; SNPs causing loss of function of CYP1A1 or CYP1A1-2 cytochrome P450 enzymes related with a lower capacity to deactivate hydrocarbons related to smoking, which involves a higher risk of developing some smoking-dependent cancers including larynx cancer., Objective: to compare the presence of null SNPs in genes GSTM1, GSTT1, and CYP1A1 rs 4646903 T>C, and CYP1A1-2 RS1048943 A>G in patients with hypopharyngeal and larynx cancer with a healthy control group., Materials and Method: The study included a total of 80 patients with hypopharyngeal and laryngeal cancer and 23 healthy subjects. Genomic DNA was obtained from saliva samples, determining genotype GSTM1 (present +, or null -), GSTT1 (present + or null -). Polymorphisms (SNP) in CYP1A1 T>C (present + CC, or absent - TC/TT), and CYP1A1-2 A>G (present + GG, or absent - AG/AA)., Results: the mean age of patients with larynx cancer was 62 years and of control subjects 63 years. Of the total sample, over 95% were men, and over 90% were smokers. The presence of null genotypes for GTM1 was 50% in patients with larynx cancer ( p = 0.042), while GSTT1 was 88.75% ( p = 0.002). CYP1A1 rs4646903 T>C polymorphisms were detected in 100% of cases of larynx cancer and 17.39% of healthy subjects ( p > 0.001)., Conclusions: patients with larynx cancer present more gene GSTM1 and GSTT1 null polymorphisms, and CYP1A1 rs4646903 T>C polymorphisms.