فهرست مطالب هانیه میرطالبی

One of the important DNA repair systems is Mismatch Repair (MMR). Mutation in this system can cause different types of cancer. Exonuclease1 (Exo1) is the only exonuclease involved in the human MMR system. Since Exo1 plays a distinctive role in the MMR system، this gene has gained a great intrest as a potential risk factor in Colorectal Cancer (CRC). Single nucleotide polymorphisms (SNP) involve in increasing or decreasing the risk of CRC. In this study، to find a potential biomarker of CRC، we investigated the association between SNP of Exo1 gene، rs1635498، and risk of colorectal cancer in patients who had referred to Taleghani hospital. This case-control study was performed on 111 cases and 121 healthy controls who had been registered in Taleghani hospital of Tehran. Genotyping analysis was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and use HPYCHVI restriction enzyme. According to our finding، while TT genotype was selected as a refrence، the frequency percent of TT، CT and CC genotypes in the patients were %90. 1، %9. 0، %0. 9 and in the control group were %92. 6، %7. 4 and %0. 0. We observed no significant difference. The frequency percent of T allele in the patients was %94. 6 and in the controls were %96. 3. Also the frequency percent of C allele were calculated in the patients and controls group respectively %5. 4 and %3. 7. The findings indicated that rs1635498 polymorphism in Exo1 gene isn''t associated with susceptibility to CRC. So، we conclude that this polymorphism doesn’t have significant role in incresing or decreasing risk of CRC.

Infection with the hepatitis C virus (HCV) is leading cause of chronic liver disease. Cytokines play a key role in the modulation of immune response. Different single-nucleotide polymorphisms (SNPs) in TNF-Alpha promoter region have been identified. The aim of this study was to investigate the association of TNF-α gene 1031 polymorphism with chronic hepatitis C patients. This study is a case-control study. Genomic DNA of 119 HCV patients infected and 120 healthy controls were extracted and their genotypes were determined by PCR (Polymerase Chain Reaction) and RFLP (Restriction Fragment Length Polymorphism). The frequency of TT, TC and CC genotypes was 88(73.9%), 31(26.1%) and (0.0%), respectively in case and it was 79(65.8%), 39(32.5%) and 2(1.7%), respectively in control (p=0.183). There was not a significant difference in genotype frequency between HCV patients and healthy control groups. The results of this study showed that there was no association between TNF-α gene 1031 polymorphism and chronic hepatitis C infection.

Transforming growth factor beta (TGF-β) has an inhibitory role in homeostasis of T-cell response and regulatory T cells and regulation of immune response against viral infections. Codon 10 of protein is located in the signal peptide and involved in secretion of cytokine. The aim of this study was to investigate the association of leu-pro polymorphism of codon 10 and hepatitis C susceptibility in patients. This case-control study was performed on 112 chronic hepatitis C patients and 122 healthy control subjects. TGF-β1 gene was amplified with PCR method and genotypes were determined using Restriction Fragment Length Polymorphism (RFLP) with MspA1I restriction enzyme. The frequency of CT genotype in both groups was higher than CC and TT. Genotyping results for CC, CT and TT states in patients was 50%, 19.6% and 30.4% and in healthy controls was 59%, 13.9% and 27.1% respectively. We found no significant difference between patients and healthy controls according to codon 10 polymorphism. According to the results of this study, no relationship was found between this protein’s genetic variations and chronic hepatitis C infection susceptibility.