A novel PAX2 heterozygous mutation in a family with Papillorenal syndrome: A case report and review of the literature.

Papillorenal syndrome (PAPRS) is a rare inherited disorder often involves abnormalities of eye and kidney. Paired box 2 (PAX2) gene, which is widely expressed in the development of the organs including kidney, ureter, eye, ear, and central nervous system has been considered an underlying cause of PAPRS. The present work aims to further our understanding of PAX2 gene and PAPRS by reporting a family with PAPRS associated with a novel PAX2 mutation and describing ocular manifestation of PAX2 mutation in previous literatures. We herein present a family with PAPRS presented with typical congenital optic disc defects and mild renal dysplasia. Through screening of candidate genes based on the next-generation sequencing, the heterozygous PAX2 mutation c.175C > T (p. Arg59Trp) was identified which had never been reported. The study expands the genetic and clinic spectrum of PAPRS. Further review of detailed ocular manifestation and genotypes of PAX2 mutation in previous study improves the recognition of the ocular phenotypes' spectrum, assists in the identification of PAPRS. Moreover, this study reveals that PAPRS is a systemic disorder with heterogeneous diverse phenotypes, and shows the importance of gene panel sequencing in the diagnosis of PAPRS which could achieve high diagnostic rates.