Our observation of low-level expression of CNTN1 protein in healthy kidney is supported by recent single cell transcriptomic profiling of human kidney, which identified CNTN1 in podocytes [29], while others have recently described CNTN1 expression in normal kidney glomeruli and co-localisation of CNTN1 and IgG4 in the glomerular basement membrane of an affected patient with MGN [30]. This evidence concerns the gene CNTN1 and idiopathic membranous glomerulonephritis.