Page 9 - 6. Ankylosing Spondylitis

Etiology

familial tendency with >90% of the risk of disease

determined genetically.

A strong association with HLA-B27 exists, particularly

in white western European populations.

oApproximately 1-2% of all people who are positive

for HLA-B27 develop ankylosing spondylitis (AS).

oThis increases to 15-20% if they also have an

affected first-degree relative.

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