Small pilot studies have discovered that several miRNAs detected in kidney biopsies or in circulation may have a prominent pathogenic role in IgAN: miRNAs 148b, 374b and let-b may regulate gd-IgA1 production, miRNAs 877-3p and 100-3p may be involved in the stimulation of mesangial cells by gd-IgA1, miRNAs 21-5p, 155, 199a-5p, 205, and 214-3p with glomerulosclerosis and interstitial fibrosis and kidney function decline [77,78,79,80,81,82]. This evidence concerns the gene PAEP and glomerulosclerosis.