Search

Introduction: Rotaviruses cause Acute Gastroenteritis (AGE) in children. Characterisation of rotavirus VP7, VP4 and VP6 genes revealed novel genotypes circulating in the region. Aim: To characterise the circulating rotavirus genotypes in Central Kerala and compare the genotypes with vaccine components to assess the genetic variability. Materials and Methods: We analysed VP6, VP4 and VP7 genes of rotavirus strains from hospitalised children (January-December 2013) by amplification, sequencing and phylogenetic analysis. VP4 and VP7 antigenic epitopes of G1P8 strains were compared with vaccine strains to determine the genetic variations. Results: G1P8 was the predominant strain, G9P8, G1P6, G9P4 were also encountered in the study. VP6 gene analysis revealed that 91.30% of strains belonged to genotype I1 and 8.7% to genotype I2. G1 and G9 strains show low nucleotide and amino acid homology with corresponding vaccine strains. Comparison between the vaccine strain and G1 study strains, eight substitutions were observed in the VP7 epitope region. In the VP4 gene (VP8 region) 22 and 12 substitutions were observed compared to Rotarix with RotaTeq vaccine strains respectively. Conclusion: Study strains clustered closely with other Indian strains, indicating common ancestral link. G1P8 strains showed low homology with vaccine strains, suggesting genetic variability to escape vaccine-derived immune response. This study helped to identify the circulating rotavirus genotypes in the region and explored possibility of emergence of divergent strains. [ABSTRACT FROM AUTHOR]

Introduction: Hepatitis B Virus (HBV) causes diverse clinical manifestations ranging from acute fulminant Hepatitis, Chronic Hepatitis (CHB) to liver cirrhosis and Haepatocellular Carcinoma (HCC). The HBV X gene (HBV-X) is a 154 amino acid multifunctional protein, mutates frequently and has a role in HBV related HCC. Aim: The current study was to explore the genetic variability and identify mutations of HBV-X in CHB patients from Central Kerala, India. Materials and Methods: The HBV-X sequences (n=39) from CHB (n=90) patients were analysed for nucleotide and amino acid diversity. Phylogenetic analyses were done using MEGA version 7.0.21 software to determine different genotypes. Results: Basal Core Promoter (BCP) mutations: A1762T/ G1764A (n=5) were found in HBeAg negative subjects (n=3, 60%). Bioinformatic analysis showed that the substitutions and mutations were HBV genotype/subgenotype specific. The predominant genotype detected was A1 (n=52, 57.77%) followed by genotype D (n=27, 30.00%). Nucleotide and amino acid diversities were more in genotype A1 than in D, which is responsible for transactivation (p<0.0001), those infected with this genotype may be at high risk for HCC. Conclusion: Genotype A1 isolates displayed most mutations/ substitutions in HBV-X, Further studies are necessary to understand its role in contributing to the development of HCC. The study represents the first formal investigation of HBV-X genetic variability in Kerala. [ABSTRACT FROM AUTHOR]