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Hereditary spastic paraplegia 50(SPG50)

MedGen UID:
442869
Concept ID:
C2752008
Disease or Syndrome
Synonyms: Spastic paraplegia 50, autosomal recessive; SPG50
 
Gene (location): AP4M1 (7q22.1)
 
Monarch Initiative: MONDO:0013048
OMIM®: 612936

Disease characteristics

Excerpted from the GeneReview: AP-4-Associated Hereditary Spastic Paraplegia
AP-4-associated hereditary spastic paraplegia (HSP), also known as AP-4 deficiency syndrome, is a group of neurodegenerative disorders characterized by a progressive, complex spastic paraplegia with onset typically in infancy or early childhood. Early-onset hypotonia evolves into progressive lower-extremity spasticity. The majority of children become nonambulatory and usually wheelchair bound. Over time spasticity progresses to involve the upper extremities, resulting in a spastic tetraplegia. Associated complications include dysphagia, contractures, foot deformities, dysregulation of bladder and bowel function, and a pseudobulbar affect. About 50% of affected individuals have seizures. Postnatal microcephaly (usually in the -2SD to -3SD range) is common. All have developmental delay. Speech development is significantly impaired and many affected individuals remain nonverbal. Intellectual disability in older children is usually moderate to severe. [from GeneReviews]
Authors:
Darius Ebrahimi-Fakhari  |  Robert Behne  |  Alexandra K Davies, et. al.   view full author information

Additional description

From NCBI curation
An autosomal recessive subtype of hereditary spastic paraplegia caused by mutation(s) in the AP4M1 gene, encoding AP-4 complex subunit mu-1.

Clinical features

From HPO
Clubfoot
MedGen UID:
3130
Concept ID:
C0009081
Congenital Abnormality
Clubfoot is a congenital limb deformity defined as fixation of the foot in cavus, adductus, varus, and equinus (i.e., inclined inwards, axially rotated outwards, and pointing downwards) with concomitant soft tissue abnormalities (Cardy et al., 2007). Clubfoot may occur in isolation or as part of a syndrome (e.g., diastrophic dysplasia, 222600). Clubfoot has been reported with deficiency of long bones and mirror-image polydactyly (Gurnett et al., 2008; Klopocki et al., 2012).
Thumbs, congenital Clasped
MedGen UID:
98140
Concept ID:
C0431886
Congenital Abnormality
In the resting position, the tip of the thumb is on, or near, the palm, close to the base of the fourth or fifth finger.
Limb hypertonia
MedGen UID:
333083
Concept ID:
C1838391
Finding
Cerebellar ataxia
MedGen UID:
849
Concept ID:
C0007758
Disease or Syndrome
Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly).
Cerebral palsy
MedGen UID:
854
Concept ID:
C0007789
Disease or Syndrome
Cerebral palsy describes a group of permanent disorders of the development of movement and posture, causing activity limitation, that are attributed to nonprogressive disturbances that occurred in the developing fetal or infant brain. The motor disorders of cerebral palsy are often accompanied by disturbances of sensation, perception, cognition, communication, and behavior, by epilepsy, and by secondary musculoskeletal problems.
Gliosis
MedGen UID:
4899
Concept ID:
C0017639
Pathologic Function
Gliosis is the focal proliferation of glial cells in the central nervous system.
Babinski sign
MedGen UID:
19708
Concept ID:
C0034935
Finding
Upturning of the big toe (and sometimes fanning of the other toes) in response to stimulation of the sole of the foot. If the Babinski sign is present it can indicate damage to the corticospinal tract.
Seizure
MedGen UID:
20693
Concept ID:
C0036572
Sign or Symptom
A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
Intellectual disability, severe
MedGen UID:
48638
Concept ID:
C0036857
Mental or Behavioral Dysfunction
Severe mental retardation is defined as an intelligence quotient (IQ) in the range of 20-34.
Hyperreflexia
MedGen UID:
57738
Concept ID:
C0151889
Finding
Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles.
Hypoplasia of the corpus callosum
MedGen UID:
138005
Concept ID:
C0344482
Congenital Abnormality
Underdevelopment of the corpus callosum.
Spastic tetraplegia
MedGen UID:
98433
Concept ID:
C0426970
Disease or Syndrome
Spastic paralysis affecting all four limbs.
Global developmental delay
MedGen UID:
107838
Concept ID:
C0557874
Finding
A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.
Cerebellar atrophy
MedGen UID:
196624
Concept ID:
C0740279
Disease or Syndrome
Cerebellar atrophy is defined as a cerebellum with initially normal structures, in a posterior fossa with normal size, which displays enlarged fissures (interfolial spaces) in comparison to the foliae secondary to loss of tissue. Cerebellar atrophy implies irreversible loss of tissue and result from an ongoing progressive disease until a final stage is reached or a single injury, e.g. an intoxication or infectious event.
Pseudobulbar signs
MedGen UID:
374006
Concept ID:
C1838579
Sign or Symptom
Pseudobulbar signs result from injury to an upper motor neuron lesion to the corticobulbar pathways in the pyramidal tract. Patients have difficulty chewing, swallowing and demonstrate slurred speech (often initial presentation) as well as abnormal behavioral symptoms such as inappropriate emotional outbursts of uncontrolled laughter or weeping etc.
Intellectual disability, progressive
MedGen UID:
337397
Concept ID:
C1846149
Mental or Behavioral Dysfunction
The term progressive intellectual disability should be used if intelligence decreases/deteriorates over time.
Ventriculomegaly
MedGen UID:
480553
Concept ID:
C3278923
Finding
An increase in size of the ventricular system of the brain.
Jaw hyperreflexia
MedGen UID:
765822
Concept ID:
C3552908
Finding
Increased intensity of muscle tendon reflexes in jaw.
Hypotonia
MedGen UID:
10133
Concept ID:
C0026827
Finding
Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.
Neonatal hypotonia
MedGen UID:
412209
Concept ID:
C2267233
Disease or Syndrome
Muscular hypotonia (abnormally low muscle tone) manifesting in the neonatal period.
Microcephaly
MedGen UID:
1644158
Concept ID:
C4551563
Finding
Head circumference below 2 standard deviations below the mean for age and gender.
Drooling
MedGen UID:
8484
Concept ID:
C0013132
Finding
Habitual flow of saliva out of the mouth.
Wide mouth
MedGen UID:
44238
Concept ID:
C0024433
Congenital Abnormality
Distance between the oral commissures more than 2 SD above the mean. Alternatively, an apparently increased width of the oral aperture (subjective).
Bulbous nose
MedGen UID:
66013
Concept ID:
C0240543
Finding
Increased volume and globular shape of the anteroinferior aspect of the nose.
High palate
MedGen UID:
66814
Concept ID:
C0240635
Congenital Abnormality
Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective).
Mandibular prognathia
MedGen UID:
98316
Concept ID:
C0399526
Finding
Abnormal prominence of the chin related to increased length of the mandible.
Narrow forehead
MedGen UID:
326956
Concept ID:
C1839758
Finding
Width of the forehead or distance between the frontotemporales is more than two standard deviations below the mean (objective); or apparently narrow intertemporal region (subjective).
Coarse facial features
MedGen UID:
335284
Concept ID:
C1845847
Finding
Absence of fine and sharp appearance of brows, nose, lips, mouth, and chin, usually because of rounded and heavy features or thickened skin with or without thickening of subcutaneous and bony tissues.
Short philtrum
MedGen UID:
350006
Concept ID:
C1861324
Finding
Distance between nasal base and midline upper lip vermilion border more than 2 SD below the mean. Alternatively, an apparently decreased distance between nasal base and midline upper lip vermilion border.
Wide nasal ridge
MedGen UID:
866473
Concept ID:
C4020718
Finding
Increased width of the nasal ridge.
Strabismus
MedGen UID:
21337
Concept ID:
C0038379
Disease or Syndrome
A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error.
Optic disc pallor
MedGen UID:
108218
Concept ID:
C0554970
Finding
A pale yellow discoloration of the optic disc (the area of the optic nerve head in the retina). The optic disc normally has a pinkish hue with a central yellowish depression.

Professional guidelines

PubMed

Viana Pinto L, Romeiro I, Gouveia F, Ramalho J, Ribeiro Silva S, Táboas Simões MI, Rodrigues Leal J
Int J Rehabil Res 2024 Mar 1;47(1):3-9. Epub 2024 Jan 20 doi: 10.1097/MRR.0000000000000607. PMID: 38251093
Aleksovska K, Kobulashvili T, Costa J, Zimmermann G, Ritchie K, Reinhard C, Vignatelli L, Fanciulli A, Damian M, Pavlakova L, Burgunder JM, Kopishinskaya S, Rakusa M, Kovacs N, Erdogan FF, Linton LR, Copetti M, Lamperti C, Servidei S, Evangelista T, Ayme S, Pareyson D, Sellner J, Krarup C, de Visser M, van den Bergh P, Toscano A, Graessner H, Berger T, Bassetti C, Vidailhet M, Trinka E, Deuschl G, Federico A, Leone MA
Eur J Neurol 2022 Jun;29(6):1571-1586. Epub 2022 Mar 23 doi: 10.1111/ene.15267. PMID: 35318776
Travaglini L, Aiello C, Stregapede F, D'Amico A, Alesi V, Ciolfi A, Bruselles A, Catteruccia M, Pizzi S, Zanni G, Loddo S, Barresi S, Vasco G, Tartaglia M, Bertini E, Nicita F
Neurogenetics 2018 May;19(2):111-121. Epub 2018 Apr 24 doi: 10.1007/s10048-018-0545-9. PMID: 29691679

Recent clinical studies

Etiology

Ebrahimi-Fakhari D, Teinert J, Behne R, Wimmer M, D'Amore A, Eberhardt K, Brechmann B, Ziegler M, Jensen DM, Nagabhyrava P, Geisel G, Carmody E, Shamshad U, Dies KA, Yuskaitis CJ, Salussolia CL, Ebrahimi-Fakhari D, Pearson TS, Saffari A, Ziegler A, Kölker S, Volkmann J, Wiesener A, Bearden DR, Lakhani S, Segal D, Udwadia-Hegde A, Martinuzzi A, Hirst J, Perlman S, Takiyama Y, Xiromerisiou G, Vill K, Walker WO, Shukla A, Dubey Gupta R, Dahl N, Aksoy A, Verhelst H, Delgado MR, Kremlikova Pourova R, Sadek AA, Elkhateeb NM, Blumkin L, Brea-Fernández AJ, Dacruz-Álvarez D, Smol T, Ghoumid J, Miguel D, Heine C, Schlump JU, Langen H, Baets J, Bulk S, Darvish H, Bakhtiari S, Kruer MC, Lim-Melia E, Aydinli N, Alanay Y, El-Rashidy O, Nampoothiri S, Patel C, Beetz C, Bauer P, Yoon G, Guillot M, Miller SP, Bourinaris T, Houlden H, Robelin L, Anheim M, Alamri AS, Mahmoud AAH, Inaloo S, Habibzadeh P, Faghihi MA, Jansen AC, Brock S, Roubertie A, Darras BT, Agrawal PB, Santorelli FM, Gleeson J, Zaki MS, Sheikh SI, Bennett JT, Sahin M
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J Neurogenet 2019 Mar;33(1):27-32. Epub 2019 Feb 12 doi: 10.1080/01677063.2019.1566326. PMID: 30747022
Ho PW, Pang SY, Li M, Tse ZH, Kung MH, Sham PC, Ho SL
Brain Behav 2015 Apr;5(4):e00321. Epub 2015 Feb 16 doi: 10.1002/brb3.321. PMID: 25798335Free PMC Article
Fink JK
Acta Neuropathol 2013 Sep;126(3):307-28. Epub 2013 Jul 30 doi: 10.1007/s00401-013-1115-8. PMID: 23897027Free PMC Article
Bourassa CV, Meijer IA, Merner ND, Grewal KK, Stefanelli MG, Hodgkinson K, Ives EJ, Pryse-Phillips W, Jog M, Boycott K, Grimes DA, Goobie S, Leckey R, Dion PA, Rouleau GA
Am J Hum Genet 2012 Sep 7;91(3):548-52. doi: 10.1016/j.ajhg.2012.07.018. PMID: 22958904Free PMC Article

Diagnosis

Méreaux JL, Banneau G, Papin M, Coarelli G, Valter R, Raymond L, Kol B, Ariste O, Parodi L, Tissier L, Mairey M, Ait Said S, Gautier C, Guillaud-Bataille M; French SPATAX clinical network, Forlani S, de la Grange P, Brice A, Vazza G, Durr A, Leguern E, Stevanin G
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J Neurogenet 2019 Mar;33(1):27-32. Epub 2019 Feb 12 doi: 10.1080/01677063.2019.1566326. PMID: 30747022
Battié MC, Lazáry A, Fairbank J, Eisenstein S, Heywood C, Brayda-Bruno M, Varga PP, McCall I
Eur Spine J 2014 Jun;23 Suppl 3:S305-14. Epub 2013 Jul 25 doi: 10.1007/s00586-013-2903-5. PMID: 23884550
Sankaranarayanan R, Nessa A, Esmy PO, Dangou JM
Best Pract Res Clin Obstet Gynaecol 2012 Apr;26(2):221-32. Epub 2011 Nov 9 doi: 10.1016/j.bpobgyn.2011.08.003. PMID: 22075441
Chinnery PF, Howell N, Andrews RM, Turnbull DM
J Med Genet 1999 Jun;36(6):425-36. PMID: 10874629Free PMC Article

Therapy

Dowling JJ, Pirovolakis T, Devakandan K, Stosic A, Pidsadny M, Nigro E, Sahin M, Ebrahimi-Fakhari D, Messahel S, Varadarajan G, Greenberg BM, Chen X, Minassian BA, Cohn R, Bonnemann CG, Gray SJ
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Mondrup K, Pedersen E
Acta Neurol Scand 1984 Apr;69(4):200-6. doi: 10.1111/j.1600-0404.1984.tb07802.x. PMID: 6377802

Prognosis

Méreaux JL, Banneau G, Papin M, Coarelli G, Valter R, Raymond L, Kol B, Ariste O, Parodi L, Tissier L, Mairey M, Ait Said S, Gautier C, Guillaud-Bataille M; French SPATAX clinical network, Forlani S, de la Grange P, Brice A, Vazza G, Durr A, Leguern E, Stevanin G
Brain 2022 Apr 29;145(3):1029-1037. doi: 10.1093/brain/awab386. PMID: 34983064
Li M, Ho PW, Pang SY, Tse ZH, Kung MH, Sham PC, Ho SL
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Kammermeier L, Spring J, Stierwald M, Burgunder JM, Reichert H
Dev Genes Evol 2003 Aug;213(8):412-5. Epub 2003 Jun 7 doi: 10.1007/s00427-003-0340-x. PMID: 12908108
Werdelin L, Keiding N
Neuroepidemiology 1990;9(6):321-31. doi: 10.1159/000110795. PMID: 2096315

Clinical prediction guides

Chen X, Dong T, Hu Y, De Pace R, Mattera R, Eberhardt K, Ziegler M, Pirovolakis T, Sahin M, Bonifacino JS, Ebrahimi-Fakhari D, Gray SJ
J Clin Invest 2023 May 15;133(10) doi: 10.1172/JCI164575. PMID: 36951961Free PMC Article
Méreaux JL, Banneau G, Papin M, Coarelli G, Valter R, Raymond L, Kol B, Ariste O, Parodi L, Tissier L, Mairey M, Ait Said S, Gautier C, Guillaud-Bataille M; French SPATAX clinical network, Forlani S, de la Grange P, Brice A, Vazza G, Durr A, Leguern E, Stevanin G
Brain 2022 Apr 29;145(3):1029-1037. doi: 10.1093/brain/awab386. PMID: 34983064
Almomen M, Martens K, Quadir A, Pontifex CS, Hanson A, Korngut L, Pfeffer G
J Neurogenet 2019 Mar;33(1):27-32. Epub 2019 Feb 12 doi: 10.1080/01677063.2019.1566326. PMID: 30747022
Solowska JM, Baas PW
Brain 2015 Sep;138(Pt 9):2471-84. Epub 2015 Jun 20 doi: 10.1093/brain/awv178. PMID: 26094131Free PMC Article
Sankaranarayanan R, Nessa A, Esmy PO, Dangou JM
Best Pract Res Clin Obstet Gynaecol 2012 Apr;26(2):221-32. Epub 2011 Nov 9 doi: 10.1016/j.bpobgyn.2011.08.003. PMID: 22075441

Recent systematic reviews

Viana Pinto L, Romeiro I, Gouveia F, Ramalho J, Ribeiro Silva S, Táboas Simões MI, Rodrigues Leal J
Int J Rehabil Res 2024 Mar 1;47(1):3-9. Epub 2024 Jan 20 doi: 10.1097/MRR.0000000000000607. PMID: 38251093

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