HLA-DR4 is also involved in some autoimmune conditions such as rheumatoid arthritis, systemic lupus erythematosus, phemphigus, obstructive hypertrophic cardiomyopathy,
IgA nephropathy, and polymyalgia rheumatica. It is associated to different ethnic groups, including Askenazi Jews.
Cases of false positive results of HIV tests have been associated to the presence of HLA-DR4, not false negative.