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Updated: Jul 8, 2026

Molecular Evolution of the Tre Recombinase
12:02

Molecular Evolution of the Tre Recombinase

Published on: May 29, 2008

Erratum

    Science (New York, N.Y.)
    |April 27, 1984
    PubMed

    Insights

    Researchers identified a parvovirus (RA-1) associated with rheumatoid arthritis. This virus contains a single-stranded DNA approximately 4.5 kilobases in size, providing key evidence for its role in the disease.

    Area of Science:

    • Virology
    • Immunology
    • Rheumatology

    Background:

    • Rheumatoid arthritis (RA) is a chronic autoimmune disease.
    • The potential role of parvoviruses in human diseases, including RA, has been investigated.
    • Previous studies suggested an association but lacked conclusive evidence.

    Purpose of the Study:

    • To provide conclusive evidence for the identity of RA-1 as a parvovirus.
    • To investigate the presence of parvovirus-like particles in patients with rheumatoid arthritis.

    Main Methods:

    • Analysis of 24-nm particles in mouse brains after inoculation with patient synovial cell extracts.
    • Detection of single-stranded DNA in CsCl gradient fractions containing infectious particles.

    Main Results:

    • 24-nm particles were not detected in normal mice or mice inoculated with extracts from noninflammatory degenerative joint disease (DJD) patients.
    • Successful extraction of single-stranded DNA (approx. 4.5 kilobases) from CsCl gradient fractions containing infectious 24-nm particles.

    Conclusions:

    • The extracted DNA provides conclusive evidence for RA-1 being a parvovirus.
    • This finding strengthens the association between parvoviruses and rheumatoid arthritis in humans.

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