Related Experiment Videos
Analysis of acquired human cytomegalovirus infections by polymerase chain reaction
J F Bale1, M E O'Neil, S S Fowler
1Department of Pediatrics, University of Iowa College of Medicine, Iowa City 52242.
Abstract:
We used the polymerase chain reaction and primers corresponding to three regions of the human cytomegalovirus (HCMV) genome to study HCMVs isolated from 16 children attending a single day-care center and the father of two children in the same center. When we analyzed isolates with primers for the pp65 and major immediate-early genes, we observed nearly uniform amplification yielding products of predicted sizes. By contrast, primers for the a sequence demonstrated variability among HCMV strains, supporting the use of these primers as an epidemiologic tool. Analysis of a-sequence products from two isolates demonstrated 50 to 70% nucleotide homology with the a sequence of HCMV Towne strain DNA. We observed 95% nucleotide homology for the two a-sequence products derived from the father-child pair. Analysis of day-care center isolates indicated that two children excreted two distinct HCMV strains during the study interval.
Insights
Human cytomegalovirus (HCMV) strains from children in a day-care center were analyzed using PCR. The HCMV
Area of Science:
- Virology
- Molecular Biology
- Epidemiology
Background:
- Human cytomegalovirus (HCMV) is a common pathogen, particularly in young children.
- Understanding HCMV transmission dynamics in settings like day-care centers is crucial for public health.
- Genetic variability within HCMV strains can aid in tracking outbreaks.
Purpose of the Study:
- To investigate the genetic diversity of HCMV strains in a day-care center population.
- To evaluate the utility of specific HCMV genomic regions as molecular markers for epidemiological studies.
- To identify potential transmission events within the studied cohort.
Main Methods:
- Polymerase chain reaction (PCR) was employed to amplify specific regions of the HCMV genome.
- Primers targeting the pp65 gene, major immediate-early (MIE) gene, and the 'a' sequence were utilized.
- Nucleotide homology analysis was performed on amplified DNA fragments.
Main Results:
- Primers for pp65 and MIE genes showed uniform amplification across HCMV isolates.
- Primers for the 'a' sequence exhibited significant variability, indicating their potential as an epidemiological tool.
- Analysis revealed 50-70% nucleotide homology with the HCMV Towne strain 'a' sequence for some isolates.
- High nucleotide homology (95%) was observed between father-child pair isolates.
- Two children were found to excrete two distinct HCMV strains during the study period.
Conclusions:
- The 'a' sequence of HCMV is a valuable genetic marker for distinguishing between different strains in epidemiological investigations.
- HCMV transmission and shedding dynamics in day-care settings can be complex, involving multiple strains.
- Close familial contact, such as between father and child, results in highly homologous HCMV strains.