Levels of cluster C12 proteins were generally lower in the serum of patients compared with that of control participants (e.g., interferon β1), whereas proteins of cluster C13 often showed uveitis subtype-specific expression patterns (e.g., endoplasmic reticulum aminopeptidase 1 in anterior uveitis; Fig 1C). The gene discussed is ERAP1; the disease is anterior uveitis.