Background: The First apoptosis signal (FAS) and First apoptosis signal ligand (FASL) GENEs initiate the apoptosis pathway, playing a central role in the tumor growth and metastasis. GENE polymorphisms including-1377 G/A in the promoter region of FAS and-844 C/T in the promoter region of FASL have shown to change the transcription activities of these GENEs. Methods: In this study we evaluated association of these polymorphisms with risk of metastasis of breast cancer, in a population selected from Mashhad, Iran. A total of 115 patients with breast cancer and 115 controls were recruited in this case-control study. Polymerase Chain Reaction-based Restriction Fragment Length Polymorphism (PCR-RFLP) was applied for genotyping on extracted DNA from participant’ s blood. Unconditional logistic regression was used to estimate cancer risk by calculating odds ratios (OR) and their 95% confidence intervals (95% CIs). Results: There was no significant association between these GENEtic polymorphisms and breast cancer risk. Additionally, our results showed no significant influence from the above mentioned GENE polymorphisms on metastasis of breast cancer. Conclusions: These results suggest that the FAS-1377G/A and FASL-844 C/T GENE polymorphism don’ t have much influence on the susceptibility to metastasis of breast cancer in northeastern Iranian population. Therefore, we suggest to investigate impact of other candidate GENE polymorphisms on metastasis of breast cancer for future research.

Background: Human cornea expresses functional FAS-ligand capable of killing FAS+ activated lymphocytes. FAS expression is partly regulated by -670 A/G polymorphism in the promoter region of FAS GENE.Objective: The aim of the present study is to determine the association between FAS-670A/G polymorphism and survival of corneal transplantation.Methods: In 276 graft recipients who mainly underwent penetrating keratoplasty because of keratoconus, bullous keratopathy and corneal opacity, FAS -670 A/G polymorphism was determined by allele specific oligonucleotide polymerase chain reaction (ASO-PCR) techniques.Results: There was no statistically significant relationship between FAS -670 A/G polymorphism and rejection episode (p=0.35). Moreover, the relationship between this polymorphism and rejection episode outcome (transplant recovery vs failure). was not statistically significant (p=0.13).Conclusion: The results of the present study show no significant correlation between corneal graft rejection, rejection recovery and FAS -670A/G GENE polymorphism.

Background: Occult hepatitis B infection (OBI) is a form of hepatitis in which there is an absence of detectable HBsAg, despite the presence of HBV-DNA in the peripheral blood of patients. It seems that non-effective or attenuated immune system responses against HBV lead to the development of OBI. Previous studies showed that the FAS/FAS ligand (FASL) system is an important death signaling pathway that is used by cytotoxic T lymphocytes to eradicate HBV from the liver.Objectives: To investigate polymorphisms in the -670 region of the FAS GENE in those with OBI. Patients and Methods: The plasma samples from 3700 blood donors were tested for HBsAg and anti- HBs by ELISA. The HBsAg-/anti-HBc+ samples were selected and screened for HBV-DNA by PCR. Those with HBV-DNA were diagnosed as OBI and PCR-RFLP technique was performed to examine polymorphisms within their FAS GENE.Results: 352 (9.5%) of 3700 blood samples were HBsAg-/anti-HBc+. HBV-DNA was detected in 57 (16.1%) of 352 HBsAg-/anti-HBc+ samples. Therefore, 57 HBsAg-/anti-HBc+/HBV-DNA+ patients were diagnosed as OBI. Patient and control groups had no significant differences in terms of the studied polymorphisms. onclusions: The functional polymorphisms in the promoter region of FAS GENE are not associated with OBI. Therefore, it may be concluded that polymorphisms at the-670 position of the FAS GENE do not have any critical effects on the immune response against HBV in OBI.