Detection and typing of molluscum contagiosum virus in skin lesions by using a simple lysis method and polymerase chain reaction

Abstract

A polymerase chain reaction (PCR) assay for the rapid detection and typing of molluscum conta giosum virus (MCV) was developed. The target DNA was a 393 base pair (bp) segment, which is present in the coding region of the MCV p43K gene product. Release of MCV DNA from skin lesions was performed by using a simple proce dure that provided suitable template DNAfor am plification, and allowed detection of MCV directly in clinical material. The PCR yielded a unique 393 bp product when MCV DNA was used as template. This product was not shown with DNA from other viruses and bacterial pathogens caus ing skin diseases. The specific PCR product was obtained with individual lesions from all patients clinically diagnosed with MCV infection, whereas no products were detected with skin samples from healthy individuals. Sequencing of this PCR product allowed determination of the virus sub type on the basis of previously described nucleo tide differences between subtypes MCVI and MCVII. To avoid the sequencing process, a sec ond PCR assay was developed, in which the tar get DNA sequence included a MCVI-specific rec ognition site for the restriction endonuclease BamHI. This PCR assay yielded a unique 575 bp product with lesions from either MCVI- or MCVII infected patients. However, only the MCVI-de rived product was susceptible to BamHl diges tion, which generated two fragments of 291 and 284 bp, respectively. Amplification of specific MCV DNA sequences from single, individual le sions provides a sensitive and reliable method for laboratory diagnosis and molecular epidemi ology studies of molluscum contagiosum.