Other tests, including serum immunoglobulins (IgA, IgG, and IgM), antinuclear antibody, acute hepatitis panel, double-stranded deoxyribonucleic acid, rheumatoid factor, complement levels (C3 and C4), and antineutrophil cytoplasmic antibody profile, all yielded negative results. The gene discussed is C4A; the disease is Acute hepatitis.