S Chantaraarphonkun1, P Bhattarakosol. 1. Inter-Department of Medical Microbiology, Graduate School, Chulalongkorn University, Bangkok, Thailand.
Abstract
OBJECTIVES: To study genotypic variations among human cytomegalovirus (HCMV) gB genotypes in clinical samples of Thai patients. METHODS: gB genotyping of 31 HCMV-DNA-positive clinical samples were determined by PCR-RFLP, gene cloning and DNA sequencing methods. RESULTS: Eight gB1, 7 gB2, 7 gB3, 6 gB untype (UT1 and UT2) and 3 mixed gB genotypes were first identified by PCR-RFLP. All 3 mixed gB genotype samples and 1 gB2 sample were cloned and confirmed gB genotype by PCR-RFLP. Altogether, 57 strains (27 unique types and 30 transformants) were further analyzed by DNA sequencing method. Discordant results between PCR-RFLP and DNA sequencing methods were demonstrated in 5 samples and 1 clone. The gB UT1 and UT2 were all classified as gB1 except 1 sample of UT1 (9D), suggesting a new variant. Each genotype had a similarity of more than 97%, whereas strains of different genotypes had 77.71-92.75% homology. The most divergent type was gB3. CONCLUSIONS: Intra- and intergenotypic variations among strains were demonstrated either in individual or distinct patients. Intragenotypic variation in a person occurs possibly due mainly to a point mutation mechanism rather than reinfection of a new gB genotype. 2007 S. Karger AG, Basel
OBJECTIVES: To study genotypic variations among human cytomegalovirus (HCMV) gB genotypes in clinical samples of Thai patients. METHODS: gB genotyping of 31 HCMV-DNA-positive clinical samples were determined by PCR-RFLP, gene cloning and DNA sequencing methods. RESULTS: Eight gB1, 7 gB2, 7 gB3, 6 gB untype (UT1 and UT2) and 3 mixed gB genotypes were first identified by PCR-RFLP. All 3 mixed gB genotype samples and 1 gB2 sample were cloned and confirmed gB genotype by PCR-RFLP. Altogether, 57 strains (27 unique types and 30 transformants) were further analyzed by DNA sequencing method. Discordant results between PCR-RFLP and DNA sequencing methods were demonstrated in 5 samples and 1 clone. The gB UT1 and UT2 were all classified as gB1 except 1 sample of UT1 (9D), suggesting a new variant. Each genotype had a similarity of more than 97%, whereas strains of different genotypes had 77.71-92.75% homology. The most divergent type was gB3. CONCLUSIONS: Intra- and intergenotypic variations among strains were demonstrated either in individual or distinct patients. Intragenotypic variation in a person occurs possibly due mainly to a point mutation mechanism rather than reinfection of a new gB genotype. 2007 S. Karger AG, Basel
Authors: Hsuan-Yuan Wang; Sarah M Valencia; Susanne P Pfeifer; Jeffrey D Jensen; Timothy F Kowalik; Sallie R Permar Journal: Viruses Date: 2021-06-09 Impact factor: 5.818