In:
Clinical Journal of the American Society of Nephrology, Ovid Technologies (Wolters Kluwer Health), Vol. 6, No. 12 ( 2011-12), p. 2766-2774
Abstract:
In a single-center renal clinic, we have established routine mutation testing to diagnose UMOD-associated kidney disease (UAKD), an autosomal dominant disorder typically characterized by gout, hyperuricemia, and renal failure in the third to sixth decades. Design, setting, participants, & measurements Four probands and their multigeneration kindreds were assessed by clinical, historical, and biochemical means. Diagnostic UMOD sequencing was performed, and mutant uromodulin was characterized in vitro . Results All available affected members of the four kindreds harbored the same complex indel change in UMOD , which was associated with almost complete absence of gout and a later onset of CKD; the youngest age at ESRD or death was 38 years (range, 38 to 68 years) compared with 3 to 70 years in other reports. Three mutation carriers (all ≤35 years) are currently asymptomatic. The indel sequence (c.278_289del TCTGCCCCGAAGinsCCGCCTCCT; p.V93_G97del/ins AASC) results in the replacement of five amino acids, including one cysteine, by four novel residues, also including a cysteine. Uromodulin staining of the only available patient biopsy suggested disorganized intracellular trafficking with cellular accumulation. Functional characterization of the mutant isoform revealed retarded intracellular trafficking associated with endoplasmic reticulum (ER) retention and reduced secretion into cell culture media, but to a lesser extent than we observed with the previously reported C150S mutation. Conclusions The indel mutation is associated with a relatively mild clinical UAKD phenotype, consistent with our in vitro analysis. UAKD should be routinely considered as a causative gene for ESRD of unknown cause, especially where there is an associated family history or where biopsy reveals interstitial fibrosis.
Type of Medium:
Online Resource
ISSN:
1555-9041
DOI:
10.2215/CJN.06820711
Language:
English
Publisher:
Ovid Technologies (Wolters Kluwer Health)
Publication Date:
2011
detail.hit.zdb_id:
2216582-4
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