 - Children 18 years of age or adults 18 or more years of age require a diagnosis of a systemic rheumatic disorder by American College of Rheumatology ACR or other criteria for the adult or juvenile forms of RA, SLE, SSc, or IIM per 92;93. Regarding the childhood-onset diseases: JRA will be defined by age of onset 17 years of age; for other diseases age of onset will be 18 years. Probands will be diagnosed within 5 years of enrollment in the study, with at least one twin or other sibling of the same gender within 5 years of age and without a recognized systemic rheumatic disorder or other autoimmune disease available for study. 