PLA2R1 and idiopathic membranous glomerulonephritis: A second antibody specific for the autoantigen thrombospondin type 1 domain–containing 7A (THSD7A) has been detected in up to 5% of patients with idiopathic membranous GN, typically in those who were seronegative for the PLA2R autoantibody (<15% cases) (45).