# Determination of whole genome sequence of human cytomegalovirus circulating in Japan and discovery of geographic genome structure in UL148 gene

## TL;DR

This study sequenced HCMV genomes from Japan, revealing a new geographic pattern in the UL148 gene among East Asian isolates.

## Contribution

The discovery of a novel geographic genome structure in the UL148 gene of HCMV in East Asia.

## Key findings

- Whole-genome sequences of two HCMV isolates from Japan were determined.
- A distinct genetic clade in the UL148 gene was identified in isolates from Japan and China.
- The study expanded the genetic database of HCMV in the East Asian region.

## Abstract

•The whole and partial genome sequences of clinical HCMV isolates in Japan were determined.•We identified a novel form of the UL148 gene in clinical isolates from Japan and China.•Phylogenetic analysis targeting the UL/b' region was conducted.•This research expanded the genetic database of HCMV and unveiled novel geographic gene structures in Asia.

The whole and partial genome sequences of clinical HCMV isolates in Japan were determined.

We identified a novel form of the UL148 gene in clinical isolates from Japan and China.

Phylogenetic analysis targeting the UL/b' region was conducted.

This research expanded the genetic database of HCMV and unveiled novel geographic gene structures in Asia.

Human cytomegalovirus (HCMV), a member of the Herpesviridae family, is prevalent worldwide. HCMV is generally asymptomatic but causes severe disease in immunocompromised patients or infants who are congenitally infected. Recent advances in sequencing technology have led to the rapid expansion of the HCMV genetic database, providing a comprehensive resource for studying viral genetics. Although genetic investigations have been vigorously performed in European countries, information on the whole-genome sequence of HCMV in the East Asian region remains limited. In this study, we determined whole-genome sequences of two clinical isolates of HCMV circulating in Japan. Partial genome sequences of 26 genes in UL/b' region were also identified using additional seven clinical isolates. Phylogenetic analysis of the UL148 gene revealed a characteristic genetic clade predominantly constructed from HCMV isolates from Japan and China, suggesting a geographic gene structure in the East Asian region. We consider that this research will contribute to expanding the genetic database of HCMV and unveiling novel genetic characteristics of HCMV in Asia.