Polymorphisms in Renal Ammonia Metabolism Genes Correlate With 24-Hour Urine pH

Urine pH is critical for net acid and solute excretion, but the genetic factors that contribute to its regulation are incompletely understood. We tested the association of single nucleotide polymorphisms (SNPs) from 16 genes related to ammonia (NH ) metabolism (15 biological candidates selected , 1 selected from a previous genome-wide association study analysis) to that of 24-hour urine pH in 2493 individuals of European descent across 2 different cohorts using linear regression, adjusting for age, sex, and body mass index. Of 2871 total SNPs in these genes, 13 SNPs in (a4 subunit of hydrogen- adenosine triphosphatase), (sodium/hydrogen exchanger, isoform 3), and (Rhesus C glycoprotein), and 12 SNPs from insulin-like growth factor binding protein 7 ( ) had a meta-analysis value