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Background: Thyroid cancer is one of the most common types of endocrine malignancies. FASL is one of the most important apoptosis ligands expressed by tumor-infiltrating lymphocytes. This death ligand plays an important role in the elimination of cancer cells by inducing apoptosis in the Fas/FasL pathway, and its disruption induces tumorigenesis. This study investigated the association of the FASL gene polymorphism - INV2nt-124A/G (rs5030772) with the risk of thyroid cancer in the East Azerbaijan region.
Materials and Methods: In this case-control study, 115 patients with thyroid cancer and 125 healthy individuals without a family history of cancer from Tabriz city were studied. Five milliliters of peripheral blood were collected from each of these participants. Proteinase K method was used for DNA extraction and FASL gene polymorphism (rs5030772) was analyzed by ARMS-PCR technique. The results were analyzed using Javastat statistics package online software.
Results: The genotype frequencies of AA, AG and GG were 40.35%, 49.12% and 10.53% in patients and 41.6%, 52.8% and 5.6% in the control group, respectively. Genotypic and allelic frequencies did not show significant differences between the patient and control groups (p>0.05). By examining the clinicopathological characteristics of the patients, no significant relationship was seen between the clinical characteristics of the patients and the distribution of the genotypes of this polymorphism (p<0.05).
Conclusion: The results of this study indicate that the FASL gene polymorphism - INV2nt-124A/G (rs5030772) cannot be considered as a risk factor for thyroid cancer in the studied population in in East Azerbaijan province.