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. 2003 Sep;40(9):671–675. doi: 10.1136/jmg.40.9.671

Genetic mapping of a new Lafora progressive myoclonus epilepsy locus (EPM2B) on 6p22

E Chan 1, D Bulman 1, A Paterson 1, J Turnbull 1, E Andermann 1, F Andermann 1, G Rouleau 1, A Delgado-Escueta 1, S Scherer 1, B Minassian 1
PMCID: PMC1735578  PMID: 12960212

Abstract

Background: Lafora disease is a progressive myoclonus epilepsy with polyglucosan accumulations and a peculiar neurodegeneration with generalised organellar disintegration. It causes severe seizures, leading to dementia and eventually death in early adulthood.

Methods: One Lafora disease gene, EPM2A, has been identified on chromosome 6q24. Locus heterogeneity led us to search for a second gene using a genome wide linkage scan in French-Canadian families.

Results: We mapped a second Lafora disease locus, EPM2B, to a 2.2 Mb region at 6p22, a region known to code for several proteins, including kinesins. Kinesins are microtubule dependent motor proteins that are involved in transporting cellular components. In neurones, they play a major role in axonal and dendritic transport.

Conclusion: Analysis of the present locus in other non-EPM2A families will reveal whether there is further locus heterogeneity. Identification of the disease gene will be of major importance towards our understanding of the pathogenesis of Lafora disease.

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Selected References

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