Founder Effect with Variable Age at Onset in Arab Families with Lafora Disease and <i>EPM2A</i> Mutation

Abstract

We conclude that considerable variability in the age at onset of Lafora disease can occur within families. Identical mutations can be associated with the classic adolescent presentation, as well as late-onset cases. Haplotype analysis suggests that this EPM2A mutation arose many generations previously, so it may be of importance for cases distributed more widely in the Middle East.