Role of Some Predominant Host Immunomodulators' Single Nucleotide Polymorphisms in Severity of Hepatitis B Virus and Hepatitis C Virus Infection

Genetic variants in IL4RA, IL6, and IL12B genes and susceptibility to hepatitis B and C virus infections among Iraqi patients

Hepatitis B and C viruses (HBV and HCV) are common causative pathogens of viral hepatitis. Progression of both infections is determined by virus- and host-related factors. Cytokines are important host genetic factors that may have a predisposing role in HBV and HCV infections. This case-control study evaluated the genetic association of IL4RA+1902 (rs1801275), IL6-174 (rs1800795), IL6-597 (rs1800797), and IL12B-1188 (rs3212227) variants with chronic HBV and HCV infections among Iraqi patients. A total of 220 viral hepatitis patients were enrolled in the study (113 HBV and 107 HCV), together with 141 healthy subjects. Sequence-specific primer polymerase chain reaction assay was the genotyping method. Results revealed that under a dominant genetic model, IL6-174 variant was significantly associated with HBV infection, whereas no association with the HCV risk was reported. However, the risk for both infections was markedly associated with IL6-597 variant under recessive, dominant, and codominant genetic models. Estimation of IL6-174 -IL6-597 haplotypes depicted that G-A haplotype was significantly associated with an increased risk to develop HBV infection, whereas a significantly decreased risk was associated with G-G and C-G haplotypes. For HCV, G-G and C-A haplotypes were significantly associated with risk of HCV infection. IL4RA+1902 and IL12B-1188 variants showed no association with HBV or HCV risk. Analysis of variance revealed no significant association between genotypes of the four determined single-nucleotide polymorphisms and HBV or HCV viral load. In conclusion, the study supports the concept that IL6-597 variant is associated with susceptibility to HBV and HCV infections among Iraqis. The risk of HBV infection is further associated with IL6-174 variant.

Analyzing Functional Pathways and constructing gene-gene network for Narcolepsy based on candidate genes

Aims: To investigate the interactions among narcolepsy-associated genes and reveal the pathways these genes involved through bioinformatics analyses. Methods: The study was performed with the following steps: 1) Selected the previously discovered narcolepsy risk genes through literature review, 2) pathway enrichment analysis, and construction of gene-gene and protein-protein interaction (PPI) networks for narcolepsy. Results: 1) GO analysis revealed the positive regulation of interferon-gamma production as the most enriched terms in biological process, and C-C chemokine receptor activity as the most enriched term in molecular function, 2) KEGG pathway enrichment analysis revealed selective enrichment of genes in cytokine-cytokine receptor interaction signaling pathways, and 3) five hub genes were identified (IFNAR1, IL10RB, DNMT1, TNFSF4 and NFATC2). Conclusion: The bioinformatics results provide new insights into the molecular pathogenesis of narcolepsy and the identification of potential therapeutic targets for narcolepsy treatment.

Host Single Nucleotide Polymorphisms Modulating Influenza A Virus Disease in Humans

A large number of human genes associated with viral infections contain single nucleotide polymorphisms (SNPs), which represent a genetic variation caused by the change of a single nucleotide in the DNA sequence. SNPs are located in coding or non-coding genomic regions and can affect gene expression or protein function by different mechanisms. Furthermore, they have been linked to multiple human diseases, highlighting their medical relevance. Therefore, the identification and analysis of this kind of polymorphisms in the human genome has gained high importance in the research community, and an increasing number of studies have been published during the last years. As a consequence of this exhaustive exploration, an association between the presence of some specific SNPs and the susceptibility or severity of many infectious diseases in some risk population groups has been found. In this review, we discuss the relevance of SNPs that are important to understand the pathology derived from influenza A virus (IAV) infections in humans and the susceptibility of some individuals to suffer more severe symptoms. We also discuss the importance of SNPs for IAV vaccine effectiveness.