J Korean Med Sci.  2003 Feb;18(1):65-68. 10.3346/jkms.2003.18.1.65.

Heterozygous Mutations of The Gene for Kir 1.1 (ROMK) in Antenatal Bartter Syndrome Presenting with Transient Hyperkalemia, Evolving to a Benign Course

• Cho JT
• Guay-Woodford LM

• KMID: 1099795
• DOI: http://doi.org/10.3346/jkms.2003.18.1.65

Abstract

Bartter-like syndrome encompasses a set of inherited renal tubular disorders associated with hypokalemic metabolic alkalosis, renal salt wasting, hyperreninemic hyperaldosteronism, and normal blood pressure. Antenatal Bartter syndrome, a subtype of Bartter-like syndrome, is characterized by polyhydramnios, premature delivery, life-threatening episodes of fever and dehydration during the early weeks of life, growth retardation, hypercalciuria, and early-onset nephrocalcinosis. Mutations in the bumetanide-sensitive Na-K-2Cl cotransporter (NKCC2) and ATP-sensitive inwardly rectifying potassium channel (ROMK) of the thick ascending limb of Henle's loop have been identified in the antenatal Bartter syndrome. We report the identification of two heterozygous mutations of the gene for Kir 1.1 (ROMK) from an antenatal Bartter syndrome patient who presented at birth with mild salt wasting and a biochemical findings that mimicked primary peudohypoaldosteronism type 1, such as hyperkalemia and hyponatremia, and evolved to a relatively benign course. We have identified amino acid exchanges Arg338Stop and Met357Thr in the gene exon 5 for ROMK by PCR and direct sequencing. Both mutations alter the C-terminus of the ROMK protein, and can affect channel function.

Keyword

Bartter's Disease; Potassium Channel; ROMK Protein; Mutation; Pseudohypoaldosteronism

MeSH Terms

Amino Acid Substitution*
Bartter's Disease/diagnosis
Bartter's Disease/embryology
Bartter's Disease/genetics*
Codon, Nonsense*
Diagnosis, Differential
Exons/genetics
Female
Heterozygote
Human
Infant, Newborn
Mutation, Missense*
Point Mutation
Potassium Channels/chemistry
Potassium Channels/genetics*
Protein Conformation
Pseudohypoaldosteronism/diagnosis