Abstract
BACKGROUND & OBJECTIVES: Various studies have suggested a correlation between Fas cell surface death receptor/Fas ligand (FAS/FASL) variants and multiple types of cancers. The present study aimed to investigate the association between FAS-670A/G and FASL-844C/T and the synergistic effects of both variants on the risk of gastric cancer (GC) in the Kurdish population of west of Iran. METHODS: This study was conducted by polymerase chain reaction-restriction fragment length polymorphism technique using MvaI and BsrDI restriction enzymes in 98 GC patients and 103 healthy control individuals. RESULTS: According to the obtained results, a significant association (P=0.008) of FASL polymorphism among GC patients and the control group was detected. Furthermore, no significant differences were found in the FAS polymorphism frequencies between GC patients and the control group. Codominant and dominant models in FASL polymorphism showed significant protective effects against GC [odds ratio (OR)=0.307, 95% confidence interval (CI) (0.134-0.705), P=0.005; OR=0.205, 95% CI (0.058-0.718), P=0.013 and OR=0.295, 95% CI (0.129-0.673), P=0.004 for models of codominant CC vs. CT, codominant CC vs. TT and dominant, respectively]. Furthermore, the presence of both FAS-670G and FASL-844T alleles represented a significant protective effect against GC occurrence [OR=0.420, 95% CI (0.181-0.975), P=0.043]. INTERPRETATION & CONCLUSIONS: So far, we believe this is the first study, the results of which suggest that FASL gene variation and its synergistic effects with FAS gene could be associated with the risk of GC in the Kurdish population in the west of Iran.