Health Dictionary Find a Doctor

HLA-B27

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]


Human Leukocyte Antigen B*27 (subtypes B*2701-2724) is a class I surface antigen encoded by the B locus in the major histocompatibility complex (MHC) on chromosome 6 and presents microbial antigens to T-cells. HLA-B27 strongly associated with a certain set of autoimmune diseases referred to as the “seronegative spondyloarthropathies“. In the general population, about 8% Caucasian, 4% African, 2-9% Chinese, and 0.1-0.5% Japanese have the HLA-B27 antigen. In Northern Scandinavia (Lapland), 24% of people are HLA-B27 positive while 1.8% have ankylosing spondylitis (AS).

Mystery

Mystery

The relationship between HLA-B27 and many diseases has not yet been fully elucidated. Though it is associated with a wide range of pathology, it does not appear to be the sole mediator in development of disease. For example, while nearly all people with ankylosing spondylitis (AS) are HLA-B27 positive, only a fraction of people with HLA-B27 ever develop AS. This raises two important questions: why don’t all HLA-B27 positive people develop AS, and why do some (although rarely) people who are HLA-B27 negative develop it? The literature is inconclusive, though several theories have been suggested and research continues.

Associated pathology

Associated pathology

In addition to its connection with AS, HLA-B27 is implicated in Reiter’s syndrome, certain eye disorders such as acute anterior uveitis and iritis, psoriatic arthritis and Crohn’s disease. Reiter’s syndrome then again, is statistically associated with AS.

See also

See also

External links

Template:HLAB

de:HLA-B27


Template:WikiDoc Sources

Looking for the patient version?

Back to the patient-friendly article

© 2026 MyEClinic – IFTM Institut für Telematik in der Medizin GmbH