HNF4A and Fanconi renotubular syndrome: Sanger DNA sequencing revealed a missense mutation located in exon 2 of HNF4A gene [EF591040.1; c.253C > T; p.R85W] (pathogenic, Fanconi syndrome, autosomal dominant) (Fig. 1C) (his parents did not carry the same variant), and he was diagnosed as Fanconi syndrome.