TY - JOUR T1 - Common variants in UMOD associate with urinary uromodulin levels: a meta-analysis. JF - J Am Soc Nephrol Y1 - 2014 A1 - Olden, Matthias A1 - Corre, Tanguy A1 - Hayward, Caroline A1 - Toniolo, Daniela A1 - Ulivi, Sheila A1 - Gasparini, Paolo A1 - Pistis, Giorgio A1 - Hwang, Shih-Jen A1 - Bergmann, Sven A1 - Campbell, Harry A1 - Cocca, Massimiliano A1 - Gandin, Ilaria A1 - Girotto, Giorgia A1 - Glaudemans, Bob A1 - Hastie, Nicholas D A1 - Loffing, Johannes A1 - Polasek, Ozren A1 - Rampoldi, Luca A1 - Rudan, Igor A1 - Sala, Cinzia A1 - Traglia, Michela A1 - Vollenweider, Peter A1 - Vuckovic, Dragana A1 - Youhanna, Sonia A1 - Weber, Julien A1 - Wright, Alan F A1 - Kutalik, Zoltán A1 - Bochud, Murielle A1 - Fox, Caroline S A1 - Devuyst, Olivier KW - Creatinine KW - European Continental Ancestry Group KW - Genetic Variation KW - Humans KW - Polymorphism, Single Nucleotide KW - Uromodulin AB -

Uromodulin is expressed exclusively in the thick ascending limb and is the most abundant protein excreted in normal urine. Variants in UMOD, which encodes uromodulin, are associated with renal function, and urinary uromodulin levels may be a biomarker for kidney disease. However, the genetic factors regulating uromodulin excretion are unknown. We conducted a meta-analysis of urinary uromodulin levels to identify associated common genetic variants in the general population. We included 10,884 individuals of European descent from three genetic isolates and three urban cohorts. Each study measured uromodulin indexed to creatinine and conducted linear regression analysis of approximately 2.5 million single nucleotide polymorphisms using an additive model. We also tested whether variants in genes expressed in the thick ascending limb associate with uromodulin levels. rs12917707, located near UMOD and previously associated with renal function and CKD, had the strongest association with urinary uromodulin levels (P<0.001). In all cohorts, carriers of a G allele of this variant had higher uromodulin levels than noncarriers did (geometric means 10.24, 14.05, and 17.67 μg/g creatinine for zero, one, or two copies of the G allele). rs12446492 in the adjacent gene PDILT (protein disulfide isomerase-like, testis expressed) also reached genome-wide significance (P<0.001). Regarding genes expressed in the thick ascending limb, variants in KCNJ1, SORL1, and CAB39 associated with urinary uromodulin levels. These data indicate that common variants in the UMOD promoter region may influence urinary uromodulin levels. They also provide insights into uromodulin biology and the association of UMOD variants with renal function.

VL - 25 IS - 8 U1 - http://www.ncbi.nlm.nih.gov/pubmed/24578125?dopt=Abstract ER -