Considering that in our center, as in most Italian and European centers involved in the routine clinical diagnosis of glomerulopathies, mass spectrophotometry techniques are not routinely performed, we retrospectively re-analyzed a cohort of 31 MN patients considered PLA2R negative (due to the absence of serum anti-PLA2R-Abs), performing glomerular microdissection and mass spectrophotometry. The gene discussed is PLA2R1; the disease is lipoprotein glomerulopathy.