A NOVEL EXOGENOUS RETROVIRUS SEQUENCE IDENTIFIED IN HUMANS

A 932-bp retrovirus sequence was cloned by reverse transcriptase PCR f rom salivary gland tissue of a patient with Sjogren's syndrome. The se quence is related to that of type B and type D retroviruses and was pr esent in a sucrose density gradient fraction corresponding to that of an enveloped retrovirus particle. Sequences amplified from tissues of eight individuals with or without Sjogren's syndrome had over 90% simi larity and were present at a level of less than one copy per 10(3) cel ls. The sequence was not detectable in human genomic DNA by PCR or by Southern hybridization. These data indicate that the sequence represen ts an infectiously acquired genome, provisionally called human retrovi rus 5.