PCDH19 mutation in Japanese females with epilepsy

Epilepsy Res. 2012 Mar;99(1-2):28-37. doi: 10.1016/j.eplepsyres.2011.10.014. Epub 2011 Nov 1.

Abstract

Purpose: To determine the significance of PCDH19 mutations in Japanese females with epilepsy and to delineate their phenotypes.

Methods: PCDH19 sequencing analysis was performed in 116 females with various epilepsies, including 97 with Dravet syndrome (83.6%). They were referred for SCN1A analysis, and 52 carried SCN1A mutations.

Results: Seven heterozygous mutations in exon 1 were identified in 7 patients (6.0%): 2 frameshift, 2 nonsense, and 3 missense mutations. One patient was a monozygotic twin, and her sister with mild phenotype carried the same mutation. The main clinical features among these 8 patients included early seizure onset (≤25 months of age), seizure clusters (7/8), fever-associated seizures (7/8), single seizure type (6/8), and late deterioration of intellect (5/8). Seizure durations were generally up to a few minutes, and only one patient developed status epilepticus once. The main seizure types were generalized tonic-clonic (4/8), tonic (3/8) and focal seizures, with (2/8) or without secondary generalization (3/8). Myoclonic, atonic and absence seizures were extremely rare. Two patients had Dravet syndrome (25%), and this proportion was significantly smaller than that in the total subjects (p<0.01).

Conclusion: PCDH19 mutation is a relatively frequent cause of epilepsy in Japanese females. Dravet syndrome was rare in our cohort.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Amino Acid Sequence
  • Asian Continental Ancestry Group / genetics*
  • Cadherins / genetics*
  • Child
  • Child, Preschool
  • Cohort Studies
  • Epilepsy / diagnosis
  • Epilepsy / genetics*
  • Female
  • Humans
  • Infant
  • Molecular Sequence Data
  • Mutation / genetics*
  • Pedigree

Substances

  • Cadherins
  • PCDH19 protein, human