Mutational analysis of CLDN 19 gene from the patients with nephrolithiasis and comparative analysis of the gene in cats and dogs

Abstract

Kidney stones (renal calculi) are solid mineral aggregates that develop in the renal system due to a combination of genetic, environmental, and biochemical factors. This study explores the genetic basis of nephrolithiasis with a focus on mutations in the CLDN 19 and SCNN1A genes, which are critical for maintaining magnesium and sodium homeostasis, respectively. Twenty families from different regions of Punjab, Pakistan, with a history of kidney stones, were selected. Clinical diagnosis was confirmed through biochemical testing and radiological imaging. Blood samples were collected from both affected and unaffected individuals, and genomic DNA was extracted using an organic method. DNA quality and concentration were assessed using agarose gel electrophoresis and NanoDrop spectrophotometry. PCR primers were designed for all exons of SCNN1A and exons 2 and 4 of CLDN19. Amplified products were purified, sequenced using Sanger sequencing, and analyzed via gel electrophoresis. Bioinformatic tools such as BLAST, PolyPhen, and Mutation Taster identified potentially pathogenic variants. Mutations in CLDN 19 may disrupt magnesium transport, while SCNN1A variants may affect sodium balance, both contributing to stone formation. These findings support the importance of genetic screening in high-risk populations and highlight the potential for improved diagnostics and personalized treatment strategies for nephrolithiasis.