a1 Department of Biochemistry, Charing Cross and Westminster Medical School, Fulham Palace Road, London W6 8RF
a2 Department of Dermatology, Charing Cross Hospital, London W6
Restriction endonuclease analysis of molluscum contagiosum virus DNA revealed two subtypes. In a study of 46 isolates from 41 patients, some with no other disorder and some with atopic dermatitis, the ratio of MCV I isolates to MCV II was 34:12. Multiple clustered lesions removed at the same time from an individual patient yielded only one type of MCV. Lesions induced by MCV I or MCV II were indistinguishable on the basis of size and form. Neither subtype was associated exclusively with lesions at certain sites or with other clinical features. Heterogeneity of DNA restriction endonuclease cleavage patterns amongst isolates of the same subtype was observed, this being greatest for MCV II.
(Accepted June 18 1987)