Isolation of a variant of BK virus with altered restriction endonuclease pattern

A papovavirus was isolated from the urine of a 24 year old female who underwent bone marrow transplantation after a relapse of acute myeloid leukemia. The virus (JL) resembles BK virus in its antigenic and growth properties, but has a different restriction endonuclease pattern after digestion with the restriction endonucleases Eco R1 and R Hind II + III.