De novo mutations in ATP1A3 cause alternating hemiplegia of childhood

Nat Genet. 2012 Sep;44(9):1030-4. doi: 10.1038/ng.2358. Epub 2012 Jul 29.

Abstract

Alternating hemiplegia of childhood (AHC) is a rare, severe neurodevelopmental syndrome characterized by recurrent hemiplegic episodes and distinct neurological manifestations. AHC is usually a sporadic disorder and has unknown etiology. We used exome sequencing of seven patients with AHC and their unaffected parents to identify de novo nonsynonymous mutations in ATP1A3 in all seven individuals. In a subsequent sequence analysis of ATP1A3 in 98 other patients with AHC, we found that ATP1A3 mutations were likely to be responsible for at least 74% of the cases; we also identified one inherited mutation in a case of familial AHC. Notably, most AHC cases are caused by one of seven recurrent ATP1A3 mutations, one of which was observed in 36 patients. Unlike ATP1A3 mutations that cause rapid-onset dystonia-parkinsonism, AHC-causing mutations in this gene caused consistent reductions in ATPase activity without affecting the level of protein expression. This work identifies de novo ATP1A3 mutations as the primary cause of AHC and offers insight into disease pathophysiology by expanding the spectrum of phenotypes associated with mutations in ATP1A3.

Publication types

  • Case Reports
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • COS Cells
  • Child
  • Chlorocebus aethiops
  • Family
  • Female
  • Genetic Predisposition to Disease
  • HeLa Cells
  • Hemiplegia / genetics*
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Male
  • Models, Biological
  • Mutation* / physiology
  • Pedigree
  • Protein Structure, Secondary
  • Sodium-Potassium-Exchanging ATPase / chemistry
  • Sodium-Potassium-Exchanging ATPase / genetics*
  • Sodium-Potassium-Exchanging ATPase / physiology

Substances

  • ATP1A3 protein, human
  • Sodium-Potassium-Exchanging ATPase

Supplementary concepts

  • Alternating hemiplegia of childhood