Association between FVL G1691A, MTHFR C677T and A1298C Polymorphisms with Risk for Retinopathy of PrematurityAssociation between FVL G1691A, MTHFR C677T and A1298C Polymorphisms with Risk for Retinopathy of Prematurity

Background: Retinopathy of prematurity (ROP) is an important cause of preventable blindness in children. The aim of this study was to examine the association of the polymorphisms at Factor V Leiden (FVL) and methylene tetrahydrofolate reductase (MTHFR) gene with risk of ROP. Methods: A total of 106 neonates with ROP and 110 healthy neonates were enrolled. The FVL G1691A and MTHFR C677T and A1298C polymorphisms were genotyped by PCR-RFLP assay. Results: There was a significant association between FVL G1691A polymorphism and an increased risk of ROP. However, the MTHFR C677T and A1298C polymorphisms were not associated with risk of ROP. Conclusion: FVL G1691A polymorphism may be risk factor for development of ROP in neonates. However, there was no significant association between MTHFR C677T and A1298C polymorphisms and risk of ROP. However, it is critical that larger and well-designed studies in different ethnicities are needed to confirm our conclusions.

Association of the Intronic Polymorphism rs3773364 A>G in Synapsin-2 Gene with Epilepsy Patients in Iraq

Epilepsy is a central nervous system disease which is characterized by a recurrent seizure that distinguishes it from other similar diseases. Epilepsy may occur due to defects in genes that encode some receptors in the brain. For this reason, this study aimed to understand the association between Synapsin-2 (SYN2) gene and susceptibility to epilepsy. Blood samples were collected from 40 volunteers, including 30 patients suffering epilepsy with an age range of 26-49 years old and 10 healthy individuals with an age range of 25-53 years old. The study sample involved 16 males and 14 females with epilepsy along with 6 males and 4 females healthy subjects. DNA was isolated from the volunteers for PCR-RFLP assay. Genotyping of rs3773364 A>G SYN2 was conducted and the results refer to a highly significant difference in the distribution of AG genotype (P=0.0001), while there is no significant difference in the distribution of AA and GG genotypes, with p values of 0.1702 and 1.00, respectively. The results also showed that gender did not significantly affect the results when comparing patients with the control (p=0.0934). Our findings indicates that SYN2 rs3773364 A>G confers risk to epilepsy and may be implicated in epileptogenesis.

PCR-based genotyping assays to detect germline APC variant associated with hereditary gastrointestinal polyposis in Jack Russell terriers

Background The prevalence of gastrointestinal (GI) neoplastic polyps in Jack Russell terriers (JRTs) has increased in Japan since the late 2000s. Recently, we demonstrated that JRTs with GI polyps harbor identical germline variant in the APC gene (c.[462_463delinsTT]) in the heterozygous state. Thus, this disease is an autosomal dominant hereditary disorder. Although the affected JRTs have distinct features, such as the development of multiple GI polyps and an early age of disease onset, genetic testing is indispensable for a definitive diagnosis. Here, polymerase chain reaction (PCR)-based assays capable of detecting germline APC variant were designed and validated using synthetic wild-type and mutant DNAs and genomic DNAs from carrier and non-carrier dogs. Result First, the PCR-restriction fragment length polymorphism (PCR-RFLP) assay was developed by taking advantage of the germline APC variant creating a new restriction site for MseI. In the PCR-RFLP assay, the 156-bp region containing the variant site was amplified by PCR and subsequently digested with MseI, yielding diagnostic 51 and 58 bp fragments from the mutant allele and allowing determination of the APC genotypes. It was possible to determine the genotypes using genomic DNA extracted from the peripheral blood, buccal swab, or formalin-fixed paraffin-embedded tissue. Next, a TaqMan duplex real-time PCR assay was developed, where a 78-bp region flanking the variant was amplified in the presence of wild-type allele- and mutant allele-specific fluorescent probes. Using blood-derived DNA, altogether 40 cycles of PCR amplification determined the APC genotypes of all examined samples by measuring the fluorescence intensities. Importantly, false-positive and false-negative errors were never detected in both assays. Conclusion In this study, we developed highly reliable genetic tests for hereditary GI polyposis in JRTs, providing accurate assessment of the presence of the causative germline APC variant. The genotyping assays could contribute to the diagnosis and prevention of hereditary GI polyposis in dogs.

The Association between C194T and G399A Polymorphism of XRCC1 Gene and Susceptibility to Gastric Cancer in Population from Western Iran

Background: Gastric cancer is one of the most common malignancies in the world. It may result from a defect in the genes involved in DNA repair. One of the essential genes in the repair pathway is the XRCC1 gene that its polymorphisms in the human population play a role in gastric cancer susceptibility. The main purpose of this study was to investigate the association of 194C/T and 399G/A polymorphisms of the XRCC1 gene with gastric cancer in an Iranian population. Materials and methods: A total of 66 patients with gastric cancer and 67 control individuals were enrolled in our study. Following DNA extraction from blood samples, polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Results: The allele frequencies of C/T of XRCC1-194C/T in the control and patients groups were 83.17% and 71.29%, respectively. Moreover, The allele frequencies of G/A of XRCC1-399G/A in control and patient groups were 66.34% and 62.38%, respectively. Our results indicated a significant positive association between the distribution T/C alleles and the risk of gastric cancer (χ2: 5.37 and P=0.02), but no significant association was found in the distribution G/A alleles (χ2: 0.47 and P=0.48). Conclusion: Altogether, these findings indicate a positive association between the distribution of 194T/C alleles of XRCC1 and the risk of gastric cancer and the presence of the C allele may increase the risk of gastric cancer.

PCR-based Genotyping Assays to Detect Germline APC mutations Associated with Hereditary Gastrointestinal Polyposis in Jack Russell Terriers

Background: The prevalence of gastrointestinal (GI) neoplastic polyps in Jack Russell Terriers (JRTs) has increased in Japan since the late 2000s. Recently, we demonstrated that JRTs with GI polyps harbor identical germline mutations in the APC gene (c.[462A>T; 463A>T]) in the heterozygous state. Thus, this disease is an autosomal dominant hereditary disorder. Although the affected JRTs have distinct features, such as the development of multiple GI polyps and an early age of disease onset, genetic testing is indispensable for a definitive diagnosis. Here, polymerase chain reaction (PCR)-based assays capable of detecting germline APC mutations were designed and validated using synthetic wild-type and mutant DNAs and genomic DNAs from carrier and non-carrier dogs.Result: First, the PCR-restriction fragment length polymorphism (PCR-RFLP) assay was developed by taking advantage of the germline APC mutations creating a new restriction site for MseI. In the PCR-RFLP assay, the 156-bp region containing the mutation site was amplified by PCR and subsequently digested with MseI, yielding diagnostic 51 and 58 bp fragments from the mutant allele and allowing determination of the APC genotypes. It was possible to determine the genotypes using genomic DNA extracted from the peripheral blood, buccal swab, or formalin-fixed paraffin-embedded tissue. Next, a TaqMan duplex real-time PCR assay was developed, where a 78-bp region flanking the mutation was amplified in the presence of wild-type allele- and mutant allele-specific fluorescent probes. Using blood-derived DNA, altogether 40 cycles of PCR amplification determined the APC genotypes of all examined samples by measuring the fluorescence intensities. Importantly, false-positive and false-negative errors were never detected in both assays. Conclusion: In this study, we developed highly reliable genetic tests for hereditary GI polyposis in JRTs, providing accurate assessment of the presence of the causative germline APC mutations. The genotyping assays could contribute to the diagnosis and prevention of hereditary GI polyposis in dogs.