Genome-wide association study of nephrolithiasis in an Eastern European population.

Abstract

Nephrolithiasis is a urological pathology that occurs at high rates and carries a great burden in terms of costs. The probability of recurrence is significant, necessitating improvements in prophylaxis and understanding of the disease mechanism. Despite the high heritability of this disease, only five genome-wide association studies (GWAS) of nephrolithiasis have been published. We selected 335 unrelated confirmed nephrolithiasis cases from two major sample collection projects (blood and buccal swabs) in Romania. DNA was extracted from whole blood and buccal swabs at deCODE Genetics (Reykjavik, Iceland) and genotyped. Single-nucleotide polymorphisms identified from this GWAS implicated biological pathways and gene ontologies involving solute transport, renal physiology, and calcium homeostasis. Three loci especially emerged as candidates with a highly significant association with nephrolithiasis: RS10917682 in Regulator of G protein signaling 5, which has crucial roles in mRNA regulation and has been linked to renal cell carcinoma; RS1118528 in Solute carrier family 25 member 24, which encodes a mitochondrial ATP-Mg/phosphate carrier protein that likely influences a variety of important cellular pathways; and the TOX2-associated locus rs4437026, because TOX2 is upregulated in several tumor types and linked to tumor progression. This study is the largest kidney stone-related GWAS reported in an Eastern European population and the first GWAS performed in a Romanian population to investigate the genetic risk factors for nephrolithiasis. We identified several loci that warrant further investigation for a better understanding of this highly heritable condition.