The anti-ETAR antibody levels in lupus nephritis patients were higher than those of the membranous nephropathy (p = 0.0001), FSGS (p = 0.0001), IgA nephropathy (p = 0.0001), and c-ANCA vasculitis (p = 0.002) groups. The gene discussed is EDNRA; the disease is focal segmental glomerulosclerosis.