Action myoclonus-renal failure syndrome (AMRF) is an autosomal recessive progressive myoclonus epilepsy (PME) associated with renal dysfunction that appears in the second or third decade of life and that is caused by loss-of-function mutations in the SCARB2 gene encoding lysosomal integral membrane protein type 2 (LIMP2).
Progressive myoclonus epilepsy: extraneuronal brown pigment deposition and system neurodegeneration in the brains of Japanese patients with novel SCARB2 mutations.
Progressive myoclonus epilepsy: extraneuronal brown pigment deposition and system neurodegeneration in the brains of Japanese patients with novel SCARB2 mutations.
Mutations of the SCARB2 gene cause action myoclonus renal failure syndrome (AMRF), a rare condition that combines progressive myoclonus epilepsy (PME) with severe renal dysfunction.
We hypothesized that mutations in SCARB2 might account for unsolved cases of progressive myoclonus epilepsy (PME) without renal impairment, especially those resembling Unverricht-Lundborg disease (ULD).
A deficiency of human LIMP-2, a receptor for lysosomal mannose 6-phosphate-independent targeting of the beta-glucosidase (betaGC), due to mutations in the SCARB2 gene was described only in six families presented with progressive myoclonic epilepsy and nephrotic syndrome.
Lafora disease (LD) is an autosomal recessive progressive myoclonus epilepsy due to mutations in the EPM2A (laforin) and EPM2B (malin) genes, with no substantial genotype-phenotype differences between the two.
Mutations in the NHL repeat containing 1 (NHLRC1) gene were described in association with a more benign clinical course and later age of death, compared with epilepsy progressive myoclonus type 2A (EPM2A) mutations.
Lafora disease (LD) is an autosomal recessive form of progressive myoclonus epilepsy with onset in childhood or adolescence and with fatal outcome caused by mutations in two genes: EPM2A and NHLRC1.
A recurrent de novo missense variant in KCNC1, encoding a voltage-gated potassium channel expressed in inhibitory neurons, causes progressive myoclonus epilepsy and ataxia, and a nonsense variant is associated with intellectual disability.
The spectrum of phenotypes associated with KCNC1 is now broadened to include not only a Progressive Myoclonus Epilepsy, but an infantile onset Developmental and Epileptic Encephalopathy, as well as Developmental Encephalopathy without seizures.
p.(Arg320His) mutation in the KCNC1 gene in human 11p15.1 has recently been identified in patients with progressive myoclonus epilepsies, a group of rare inherited disorders manifesting with action myoclonus, myoclonic epilepsy, and ataxia.