SLC52A2 and renal tubular dysgenesis of genetic origin: Starting from 2010, RTD, formerly known as Brown-Vialetto-Van Laere (BVVL) syndrome, was found to be caused by biallelic pathogenic variants in either SLC52A2 or SLC52A3 genes [14], and over 75 (mostly nonsense and missense mutations) in both genes have been associated with RTD.