Referenced in: none

Automatically associated channels: ClC4 , ClCK2

Title: Molecular analysis of the CLCNKB gene in Japanese patients with classic Bartter syndrome.

Authors: Toshihiro Tajima, Mitsuru Nawate, Yutaka Takahashi, Yumiko Mizoguchi, Shigetaka Sugihara, Masaaki Yoshimoto, Mutsumi Murakami, Masanori Adachi, Katsuhiko Tachibana, Hiroshi Mochizuki, Kenji Fujieda

Journal, date & volume: Endocr. J., 2006 Oct , 53, 647-52

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/16902263

Abstract
Deletions or mutations in the gene encoding the basolateral chloride channel CLC-Kb (CLCNKB) cause classic Bartter syndrome (MIM 602023), which is characterized by hypokalemic metabolic alkalosis, hyperreninemic hyperaldosteronism and hypercalciura. These patients are usually diagnosed during infancy or childhood due to failure to thrive and growth retardation. The purpose of this study was to investigate the underlying mutations in Japanese patients with classic Bartter syndrome. Seven Japanese patients from seven different families diagnosed as having classic Bartter syndrome were studied. Analysis of CLCNKB demonstrated a large deletion in two patients, a partial deletion in one patient and two mutations (DeltaL130 in exon 4 and W610X in exon 16) in the remaining four patients. DeltaL130 is a novel mutation, but W610X was previously reported in three unrelated Japanese patients. Six out of the seven patients were diagnosed due to typical characteristics of classic Bartter syndrome such as failure to thrive and poor weight gain however, one patient was asymptomatic with mild hypokalemia. In conclusion, we identified a novel mutation of the CLCNKB gene, DeltaL130. We did not determine whether the W610X mutation in our patients was from a common ancestor or if this mutation is frequent in Japan.