Preferred Label : Myoclonic epilepsy of lafora 1;
Symbol : MELF1;
CISMeF acronym : EPM2A; EPM2B; EPM2; LBD; MELF;
Type : Phenotype, molecular basis known;
Alternative titles and symbols : Lafora disease; Lafora body disease; Epilepsy, progressive myoclonic, 2a; MELF; LBD; EPM2A; EPM2; Lafora disease 1;
Description : The Lafora type of progressive myoclonic epilepsy is an autosomal recessive disorder
characterized by insidious onset of progressive neurodegeneration between 8 and 18
years of age. Initial features can include headache, difficulties in school work,
myoclonic jerks, generalized seizures, and often visual hallucination. The myoclonus,
seizures, and hallucinations gradually worsen and become intractable. This is accompanied
by progressive cognitive decline, resulting in dementia. About 10 years after onset,
affected individuals are in near-continuous myoclonus with absence seizures, frequent
generalized seizures, and profound dementia or a vegetative state. Histologic studies
of multiple tissues, including brain, muscle, liver, and heart show intracellular
Lafora bodies, which are dense accumulations of malformed and insoluble glycogen molecules,
termed polyglucosans (review by Ramachandran et al., 2009). For a discussion of genetic
heterogeneity of progressive myoclonic epilepsy, see EPM1A (254800).;
Inheritance : Autosomal recessive;
Molecular basis : Caused by mutation in the malin gene (NHLRC1, 608072.0001); Caused by mutation in the laforin gene (EPM2A, 607566.0001);
Laboratory abnormalities : Intracellular PAS-positive polyglucosan inclusion bodies ('Lafora' bodies) can be
found in various tissues (brain, liver, muscle, heart, skin);
Prefixed ID : #254780;
Origin ID : 254780;
UMLS CUI : C5848203;
Automatic exact mappings (from CISMeF team)
Currated CISMeF NLP mapping
DO Cross reference
Genes related to phenotype
HPO term(s)
ORDO concept(s)
Semantic type(s)
UMLS correspondences (same concept)