title: A novel splice site mutation of the beta subunit gene of epithelial sodium channel (ENaC) in one Turkish patient with a systemic form of pseudohypoaldosteronism Type 1.
abstract: OBJECTIVE
  Pseudohypoaldosteronism Type 1 (PHA1) is a rare heterogeneous syndrome characterized by severe salt loss, hyperkalemia, hyponatremia, metabolic acidosis, hyperaldosteronism and hyperreninemia. Multi-system form of PHA1 is caused by mutations in one of the genes encoding the α, β and γ subunits of epithelial sodium channels (ENaC). In this study, we presented a novel splice site mutation in the beta-gene of ENaC in a patient with multi-system PHA.
  
  
  METHODS
  We performed DNA sequencing analysis of SCNN1A, SCNN1B, SCNN1G and NR3C2 genes.
  
  
  RESULTS
  We found a novel c.1266-1G>C homozygous splice site mutation in intron 8 of the SCNN1B gene. Initially elevated plasma renin activity (PRA) and aldosterone levels of the patient returned to normal with large amounts of dietary salt and serum sodium (Na+) and potassium (K+) levels were within normal range at the end of the first year of life.
  
  
  CONCLUSIONS
  This improvement may be due to partial activity of mutated ENaC subunits, reduced dependence on aldosterone in salt homeostasis with increasing age, and alternative regulating mechanisms in sodium homeostasis. The results enhance our understanding of the pathophysiology of this disorder and the mechanisms of renal salt conservation.
authors: Department of Pediatric Nephrology, Akdeniz University, Antalya, Turkey. d.caglaserpil@yahoo.com
authors: Cagla Serpil
authors: CS
authors: Dogan
authors: Durmaz
authors: D
authors: Erdem
authors: Parlak
authors: P
authors: Mesut
authors: Akan
authors: A
authors: Merve
authors: Akcurin
authors: A
authors: Sema
authors: Bircan
authors: B
authors: Iffet
authors: Berdeli
authors: B
authors: Afig
mesh_terms: D053503:Epithelial Sodium Channels / Q000235:genetics*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009154:Mutation; D011546:Pseudohypoaldosteronism / Q000235:genetics*; D022821:RNA Splice Sites
chemical_list: D053503:Epithelial Sodium Channels; D022821:RNA Splice Sites; C507048:SCNN1B protein, human