Spinal muscular atrophy with progressive myoclonic epilepsy

Other names: Hereditary myoclonus-progressive distal muscular atrophy syndrome
This condition is inherited in an autosomal recessive manner
Specialty| Neurology

Spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME), sometimes called Jankovic–Rivera syndrome, is a very rare neurodegenerative disease whose symptoms include slowly progressive muscle (atrophy), predominantly affecting proximal muscles, combined with denervation and myoclonic seizures.[1] Only 12 known human families are described in scientific literature to have SMA-PME.[2]

SMA-PME is associated with a missense mutation (c.125C→T) or deletion in exon 2 of the ASAH1 gene and is inherited in an autosomal recessive manner.[3] SMA-PME is closely related to a lysosomal disorder disease called Farber lipogranulomatosis.[4] As with many genetic disorders, there is no known cure for SMA-PME.

The condition was first described in 1979 by American researchers Joseph Jankovic and Victor M. Rivera.[5]

The ASAH1 gene codes for acid ceramidase, an enzyme found in lysosomes. The lysosome breaks down acid ceramidase; the fatty acid component [6] is then used to produce myelin. Myelin is an insulating coating around the neurons in the body which helps to contain bioelectrical signals along a nerve cell's axon and increase transmission rate.[7] In patients with SMA-PME, the ceramidase function decreases to 33.33% effective.[2] The lack of myelin resulting from the lack of acid ceramidase breakdown leads to nerve cell dysfunction.[citation needed]

EEG with generalized spike and wave complexes

## See also[edit | edit source]

* Spinal muscular atrophies
* Progressive myoclonus epilepsy

## References[edit | edit source]

1. ↑ Haliloglu, G.; Chattopadhyay, A.; Skorodis, L.; Manzur, A.; Mercuri, E.; Talim, B.; Akçören, Z.; Renda, Y.; Muntoni, F.; Topaloğlu, H. (2002). "Spinal Muscular Atrophy with Progressive Myoclonic Epilepsy: Report of New Cases and Review of the Literature". Neuropediatrics. 33 (6): 314–319. doi:10.1055/s-2002-37087. PMID 12571787.
2. ↑ 2.0 2.1 Reference, Genetics Home. "Spinal muscular atrophy with progressive myoclonic epilepsy". Genetics Home Reference. Archived from the original on 2020-10-01. Retrieved 2018-09-24.
3. ↑ Zhou, J.; Tawk, M.; Tiziano, F. D.; Veillet, J.; Bayes, M.; Nolent, F.; Garcia, V.; Servidei, S.; Bertini, E.; Castro-Giner, F.; Renda, Y.; Carpentier, S. P.; Andrieu-Abadie, N.; Gut, I.; Levade, T.; Topaloglu, H.; Melki, J. (2012). "Spinal Muscular Atrophy Associated with Progressive Myoclonic Epilepsy is Caused by Mutations in ASAH1". The American Journal of Human Genetics. 91 (1): 5–14. doi:10.1016/j.ajhg.2012.05.001. PMC 3397266. PMID 22703880.
4. ↑ Gan, Joanna J.; Garcia, Virginie; Tian, Jane; Tagliati, Michele; Parisi, Joseph E.; Chung, Jeffrey M.; Lewis, Richard; Baloh, Robert; Levade, Thierry; Pierson, Tyler Mark (2015-12-01). "Acid ceramidase deficiency associated with spinal muscular atrophy with progressive myoclonic epilepsy". Neuromuscular Disorders. 25 (12): 959–963. doi:10.1016/j.nmd.2015.09.007. ISSN 0960-8966. PMID 26526000.
5. ↑ Jankovic, J.; Rivera, V. M. (1979). "Hereditary myoclonus and progressive distal muscular atrophy". Annals of Neurology. 6 (3): 227–231. doi:10.1002/ana.410060309. PMID 534421.
6. ↑ Park, Jae-Ho; Schuchman, Edward H. (December 2006). "Acid ceramidase and human disease". Biochimica et Biophysica Acta (BBA) - Biomembranes. 1758 (12): 2133–2138. doi:10.1016/j.bbamem.2006.08.019. ISSN 0006-3002. PMID 17064658.
7. ↑ Morell, Pierre; Quarles, Richard H. (1999). "The Myelin Sheath". Basic Neurochemistry: Molecular, Cellular and Medical Aspects. 6th Edition. Archived from the original on 2020-11-11. Retrieved 2022-05-05.

## Further reading[edit | edit source]

* National Institutes of Health (December 2013). "Genetics Home Reference: Spinal muscular atrophy with progressive myoclonic epilepsy". Archived from the original on 2020-10-01. Retrieved 2022-05-05.

## External links[edit | edit source]

Classification|

* ICD-10: G25.3
* OMIM: 159950

|

External resources|

* Orphanet: 2590

* v
* t
* e

Diseases of the nervous system, primarily CNS

Inflammation|

| Brain|

* Encephalitis
* Viral encephalitis
* Herpesviral encephalitis
* Limbic encephalitis
* Encephalitis lethargica
* Cavernous sinus thrombosis
* Brain abscess
* Amoebic

|

Brain and spinal cord|

* Encephalomyelitis
* Acute disseminated
* Meningitis
* Meningoencephalitis

Brain/
encephalopathy|

| Degenerative|

| Extrapyramidal and
movement disorders|

* Basal ganglia disease
* Parkinsonism
* PD
* Postencephalitic
* NMS
* PKAN
* Tauopathy
* PSP
* Striatonigral degeneration
* Hemiballismus
* HD
* OA

* Dyskinesia
* Dystonia
* Status dystonicus
* Spasmodic torticollis
* Meige's
* Blepharospasm
* Athetosis
* Chorea
* Choreoathetosis
* Myoclonus
* Myoclonic epilepsy
* Akathisia

* Tremor
* Essential tremor
* Intention tremor
* Restless legs
* Stiff-person

|

Dementia|

* Tauopathy
* Alzheimer's
* Early-onset
* Primary progressive aphasia
* Frontotemporal dementia/Frontotemporal lobar degeneration
* Pick's
* Dementia with Lewy bodies
* Posterior cortical atrophy

* Vascular dementia

Mitochondrial disease|

* Leigh syndrome

Demyelinating|

* Autoimmune
* Inflammatory
* Multiple sclerosis
* For more detailed coverage, see Template:Demyelinating diseases of CNS

Episodic/
paroxysmal|

| Seizures and epilepsy|

* Focal
* Generalised
* Status epilepticus
* For more detailed coverage, see Template:Epilepsy

|

Headache|

* Migraine
* Cluster
* Tension
* For more detailed coverage, see Template:Headache

Cerebrovascular|

* TIA
* Stroke
* For more detailed coverage, see Template:Cerebrovascular diseases

Other|

* Sleep disorders
* For more detailed coverage, see Template:Sleep

CSF|

* Intracranial hypertension
* Hydrocephalus
* Normal pressure hydrocephalus
* Choroid plexus papilloma
* Idiopathic intracranial hypertension
* Cerebral edema
* Intracranial hypotension

Other|

* Brain herniation
* Reye syndrome
* Hepatic encephalopathy
* Toxic encephalopathy
* Hashimoto's encephalopathy

Both/either|

| Degenerative|

| SA|

* Friedreich's ataxia
* Ataxia–telangiectasia

|

MND|

* UMN only:
* Primary lateral sclerosis
* Pseudobulbar palsy
* Hereditary spastic paraplegia

* LMN only:
* Distal hereditary motor neuronopathies
* Spinal muscular atrophies
* SMA
* SMAX1
* SMAX2
* DSMA1
* Congenital DSMA
* Spinal muscular atrophy with lower extremity predominance (SMALED)
* SMALED1
* SMALED2A
* SMALED2B
* SMA-PCH
* SMA-PME
* Progressive muscular atrophy
* Progressive bulbar palsy
* Fazio–Londe
* Infantile progressive bulbar palsy

* both:
* Amyotrophic lateral sclerosis

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