Human Cytomegalovirus US28 Genomic Variation Among Infants at a Tertiary Care Hospital From Eastern India

Human cytomegalovirus (HCMV) poses a significant global health threat, particularly to newborns and immunocompromised individuals. HCMV exhibits extensive genetic diversity, and a specific genotype may be associated with virulence. HCMV US28 encodes for a chemokine receptor that plays a role in cellular processes and in pathogenesis. In this study, we investigated the HCMV US28 genotype distribution in infants.

72 suspected infants during the study period were included in the study. Deoxyribonucleic acid (DNA) was extracted from clinical specimens using the spin column method, and the US28 ORF target gene was amplified using the US28-specific nested polymerase chain reaction (PCR). The housekeeping β-globin gene was amplified in each run. Amplified US28 gene products were PCR purified, and genotypes were discriminated by Sanger sequencing. Selected sequences were submitted to the National Center for Biotechnology Information (NCBI), USA, and accession numbers were obtained.

Of the 72 infants examined, 21 were amplified for the US28 region using nested PCR. The sequencing revealed that the majority of the US28 fall in the A2 genotype in 80% and 20% in the A1 group. Single-nucleotide polymorphisms (SNPs) are seen in the sequences. Our findings show no significant association of a specific genotype with symptomatic HCMV infection.

This study reports that the US28 A2 genotype is prevalent in this region. This study is of value in understanding the epidemiology of circulating strains in this region. Further studies are required from different geographical regions with larger sample sizes to get the true picture of the findings.