Identification of novel mutations in Na-Cl cotransporter gene in a Korean patient with atypical Gitelman's syndrome.
The authors report the case of a 20-year-old man with unexplained hypokalemia and metabolic alkalosis suggesting hypokalemic tubulopathy. Interestingly, he showed a mixed phenotype of Gitelman's syndrome (GS) and Bartter's syndrome, which includes normomagnesemia, normal renal magnesium excretion, and hypocalciuria. Renal clearance study showed the presence of a critical defect in the distal nephron rather than loop of Henle. Further family study showed that his mother had a definitive phenotype of GS. By the molecular genetic analysis of these patients, 7 different mutations of the NCCT gene were identified consisting of 3 missense, 1 splice site, and 3 silent mutations. Four of these mutations were novel. The authors emphasize that the combination of a molecular genetic approach and renal clearance study could be of practical benefit in confusing clinical setting and support new diagnostic criteria in GS.
Yoo
Tae-Hyun
TH
TOP Department of Nephrology, Yonsei University College of Medicine, Seoul, South Korea.
Lee
Sang-Ho
SH
Yoon
KyungSik
K
Baek
HaengWoon
H
Chung
Joo-Ho
JH
Lee
TaeWon
T
Ihm
ChunGyoo
C
Kim
MyungJae
M
D000328:Adult; D000471:Alkalosis / Q000235:genetics; D019943:Amino Acid Substitution; D001477:Bartter Syndrome / Q000175:diagnosis / Q000235:genetics; D002118:Calcium / Q000652:urine; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D005091:Exons / Q000235:genetics; D005260:Female; D006801:Humans; D007008:Hypokalemia / Q000235:genetics; D020514:Hypokalemic Periodic Paralysis / Q000235:genetics*; D007438:Introns / Q000235:genetics; D007723:Korea; D008274:Magnesium / Q000097:blood; D008297:Male; D016254:Mutagenesis, Insertional; D009154:Mutation; D020125:Mutation, Missense; D010641:Phenotype; D022821:RNA Splice Sites / Q000235:genetics; D011955:Receptors, Drug; D015499:Renal Tubular Transport, Inborn Errors / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism; D049992:Sodium Chloride Symporters; D064486:Solute Carrier Family 12, Member 3; D027981:Symporters; D013577:Syndrome
D002352:Carrier Proteins; D022821:RNA Splice Sites; D011955:Receptors, Drug; C578874:SLC12A3 protein, human; D049992:Sodium Chloride Symporters; D064486:Solute Carrier Family 12, Member 3; D027981:Symporters; C064415:thiazide receptor; D008274:Magnesium; D002118:Calcium