Diagnostic biomarkers have long remained elusive; however, circulating autoantibodies against nephrin have recently been identified in patients with primary podocytopathies and were shown to strongly correlate with disease activity.1, 2, 3, 4 Importantly, patient-derived antinephrin positive IgG was demonstrated to induce proteinuria, nephrin phosphorylation, and a minimal change disease–like histotype upon transfer to a rabbit, thereby supporting a direct pathogenic role of these autoantibodies.5 Here, NPHS1 is linked to lipoid nephrosis.