Auxiliary genetic analysis in a Chinese adolescent NPH family by single nucleotide polymorphism screening

Hereditary nephropathy is a progressive fatal renal disease caused by genetic changes. In this study, genetic screening was used to reveal mutations in a family in Southern China, in which there are two patients with confirmed hereditary nephropathy, who are alive at the time of publication. Imaging tests, including color Doppler ultrasonography and magnetic resonance imaging (MRI), as well as pathological examinations, including hematoxylin-eosin staining, electron microscopy and immunohistochemistry were performed. Target sequencing of nephrosis 2 (NPHS2), wilms tumor 1 (WT1), phospholipase C ε 1 (PLCE1), actinin α 4 (ACTN4), angiotensin I converting enzyme (ACE), uromodulin (UMOD) and nephrocystin 1 (NPHP1) was also carried out. This study indicated that heterozygous genetic variants of NPHS2, WT1, ACTN4, PLCE1 and UMOD found in the patients were gene polymorphisms. A renal biopsy showed sclerosing glomerulonephritis, dilated tubules and lymphocyte/monocyte infiltration in the interstitium of the index patients. Genetic analysis showed vertical transmission of the disease-causing mutations, including a homozygous deletion in NPHP1 and a nonsense mutation in ACE found via PCR-based single nucleotide polymorphism screening. Further network analysis identified direct and indirect co-location genes between NPHP1 and ACE. To conclude, familial adolescent nephronophthisis was diagnosed in two index patients in this study. It is recommended that comprehensive gene mutation screening is used in the diagnosis of complex hereditary diseases.