The progressive myoclonus epilepsies (PMEs) are a group of predominantly recessive disorders that present with action myoclonus, tonic-clonic seizures, and progressive neurological decline. Many PMEs have similar clinical presentations yet are genetically heterogeneous, making accurate diagnosis difficult. A locus for PME was mapped in a consanguineous family with a single affected individual to chromosome 17q21. An identical-by-descent, homozygous mutation in GOSR2 (c.430G>T, p.Gly144Trp), a Golgi vesicle transport gene, was identified in this patient and in four apparently unrelated individuals. A comparison of the phenotypes in these patients defined a clinically distinct PME syndrome characterized by early-onset ataxia, action myoclonus by age 6, scoliosis, and mildly elevated serum creatine kinase. This p.Gly144Trp mutation is equivalent to a loss of function and results in failure of GOSR2 protein to localize to the cis-Golgi.

dx.doi.org/10.1016/j.ajhg.2011.04.011, hdl.handle.net/1765/33438
American Journal of Human Genetics
Erasmus MC: University Medical Center Rotterdam

Corbett, M.A, Schwake, M, Bahlo, M, Dibbens, L.M, Lin, M, Gandolfo, L.C, … Berkovic, S.F. (2011). A mutation in the Golgi Qb-SNARE gene GOSR2 causes progressive myoclonus epilepsy with early ataxia. American Journal of Human Genetics, 88(5), 657–663. doi:10.1016/j.ajhg.2011.04.011