Clinical and Immunogenetic Characterization of Giant Cell Arteritis (GCA) and Polymyalgia Rheumatica (PMR)

Who May Qualify: - Willing to self-identify an ethnic group, such as Caucasian, Asian, Afro-Caribbean. - Have a firm clinical diagnosis of GCA or PMR, or (for patients identified prospectively) GCA or PMR should be more likely than any alternative explanation for the patient's symptoms. - Able and willing to give willing to sign a consent form. Patients will be 50 years of age or over, unless both biopsy-proven and a clinically classical case of GCA. Who Should NOT Join This Trial: • Patient unwilling or unable to give fully willing to sign a consent form. Always talk to your doctor about whether this trial is right for you.