Is there a predisposition or cause for ankylosing spondylitits?
The genes HLA-B27, IL23R, and ERAP1 do not cause AS on their own. These genes represent a predisposition, or increased risk for developing ankylosing spondylitis. It is important to remember these genes do not cause AS by themselves. Risk factors that predispose a person to AS include testing positive for the HLA-B27 marker, a family history of AS, and/or frequent gastrointestinal infections.