Format

Send to:

Choose Destination

Links from Books

Troyer syndrome(SPG20)

MedGen UID:
97950
Concept ID:
C0393559
Disease or Syndrome
Synonyms: Autosomal recessive spastic paraplegia type 20; Spastic paraparesis childhood-onset with distal muscle wasting; Spastic paraplegia 20; Spastic paraplegia autosomal recessive Troyer type; SPG20
Modes of inheritance:
Autosomal recessive inheritance
MedGen UID:
141025
Concept ID:
C0441748
Intellectual Product
Sources: HPO, OMIM, Orphanet
A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in homozygotes. In the context of medical genetics, autosomal recessive disorders manifest in homozygotes (with two copies of the mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele).
Autosomal recessive inheritance (HPO, OMIM, Orphanet)
SNOMED CT: Troyer syndrome (230264003)
 
Gene (location): SPG20 (13q13.3)
OMIM®: 275900
Orphanet: ORPHA101000

Disease characteristics

Excerpted from the GeneReview: Troyer Syndrome
Troyer syndrome is characterized by progressive spastic paraparesis, dysarthria, and pseudobulbar palsy; distal amyotrophy; motor and cognitive delays; short stature; and subtle skeletal abnormalities. Most affected children exhibit delays in walking and talking followed by slow deterioration in both gait and speech. Emotional lability and affective disorders, such as inappropriate euphoria and/or crying, are common. Mild cerebellar signs are common. The most severely affected individuals have choreoathetosis. Life expectancy is normal. [from GeneReviews]
Authors:
Heema Patel  |  Gaurav Harlalka  |  Andrew Crosby   view full author information

Additional description

From GHR
Troyer syndrome is part of a group of genetic disorders known as hereditary spastic paraplegias. These disorders are characterized by progressive muscle stiffness (spasticity) and the development of paralysis of the lower limbs (paraplegia). Hereditary spastic paraplegias are divided into two types: pure and complex. The pure types involve the lower limbs. The complex types involve the lower limbs and can also affect the upper limbs to a lesser degree; the structure or functioning of the brain; and the nerves connecting the brain and spinal cord to muscles and sensory cells that detect sensations such as touch, pain, heat, and sound (the peripheral nervous system). Troyer syndrome is a complex hereditary spastic paraplegia.People with Troyer syndrome can experience a variety of signs and symptoms. The most common characteristics of Troyer syndrome are spasticity of the leg muscles, progressive muscle weakness, paraplegia, muscle wasting in the hands and feet (distal amyotrophy), small stature, developmental delay, learning disorders, speech difficulties (dysarthria), and mood swings. Other characteristics can include exaggerated reflexes (hyperreflexia) in the lower limbs, uncontrollable movements of the limbs (choreoathetosis), skeletal abnormalities, and a bending outward (valgus) of the knees.Troyer syndrome causes the degeneration and death of muscle cells and motor neurons (specialized nerve cells that control muscle movement) throughout a person's lifetime, leading to a slow progressive decline in muscle and nerve function. The severity of impairment related to Troyer syndrome increases as a person ages. Most affected individuals require a wheelchair by the time they are in their fifties or sixties.  https://ghr.nlm.nih.gov/condition/troyer-syndrome

Clinical features

Hypertelorism
MedGen UID:
9373
Concept ID:
C0020534
Congenital Abnormality
Although hypertelorism means an excessive distance between any paired organs (e.g., the nipples), the use of the word has come to be confined to ocular hypertelorism. Hypertelorism occurs as an isolated feature and is also a feature of many syndromes, e.g., Opitz G syndrome (145410), Greig cephalopolysyndactyly (175700), and Noonan syndrome (163950) (summary by Cohen et al., 1995).
Brachydactyly
MedGen UID:
67454
Concept ID:
C0221357
Congenital Abnormality
Digits that appear disproportionately short compared to the hand/foot. The word brachydactyly is used to describe a series of Mendelian diseases characterized by distinct patterns of shortened digits (brachydactyly types A-E). This is the sense used here, however, it is preferable to described the observed phenotypic abnormalities precisely.
Ankle clonus
MedGen UID:
68672
Concept ID:
C0238651
Finding
Clonus is an involuntary tendon reflex that causes repeated flexion and extension of the foot. Ankle clonus is tested by rapidly flexing the foot upward.
Clinodactyly
MedGen UID:
120550
Concept ID:
C0265610
Congenital Abnormality
An angulation of a digit at an interphalangeal joint in the plane of the palm (finger) or sole (toe).
Monoparesis - leg
MedGen UID:
605376
Concept ID:
C0427068
Finding
Weakness of the muscles of the legs.
Pes cavus
MedGen UID:
675590
Concept ID:
C0728829
Congenital Abnormality
The presence of an unusually high plantar arch. Also called high instep, pes cavus refers to a distinctly hollow form of the sole of the foot when it is bearing weight.
Hammertoe
MedGen UID:
209712
Concept ID:
C1136179
Anatomical Abnormality
Hyperextension of the metatarsal-phalangeal joint with hyperflexion of the proximal interphalangeal (PIP) joint.
Short foot
MedGen UID:
376415
Concept ID:
C1848673
Finding
A measured foot length that is more than 2 SD below the mean for a newborn of 27 - 41 weeks gestation, or foot that is less than the 3rd centile for individuals from birth to 16 years of age (objective). Alternatively, a foot that appears disproportionately short (subjective).
Short stature
MedGen UID:
87607
Concept ID:
C0349588
Finding
Height greater than two standard deviations below the mean of the appropriate reference population for the age and sex of the individual.
Drooling
MedGen UID:
8484
Concept ID:
C0013132
Sign or Symptom
Habitual flow of saliva out of the mouth.
Dysarthria
MedGen UID:
8510
Concept ID:
C0013362
Mental or Behavioral Dysfunction
Dysarthric speech is a general description referring to a neurological speech disorder characterized by poor articulation. Depending on the involved neurological structures, dysarthria may be further classified as spastic, flaccid, ataxic, hyperkinetic and hypokinetic, or mixed.
Intellectual disability, mild
MedGen UID:
10044
Concept ID:
C0026106
Mental or Behavioral Dysfunction
Mild intellectual disability is defined as an intelligence quotient (IQ) in the range of 50-69.
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.
Spastic paraparesis
MedGen UID:
52432
Concept ID:
C0037771
Sign or Symptom
Mild or moderate loss of motor function accompanied by spasticity in the lower extremities. This condition is a manifestation of CENTRAL NERVOUS SYSTEM DISEASES that cause injury to the motor cortex or descending motor pathways.
Spastic paraplegia
MedGen UID:
20882
Concept ID:
C0037772
Disease or Syndrome
Spasticity and weakness of the leg and hip muscles.
Mood swings
MedGen UID:
39319
Concept ID:
C0085633
Mental or Behavioral Dysfunction
An exaggeration of emotional affects such as laughing crying, or yawning beyond what the person feels.
Hyperreflexia
MedGen UID:
57738
Concept ID:
C0151889
Finding
Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles.
Spastic gait
MedGen UID:
115907
Concept ID:
C0231687
Finding
Dysmetria
MedGen UID:
68583
Concept ID:
C0234162
Finding
A type of ataxia characterized by the inability to carry out movements with the correct range and motion across the plane of more than one joint related to incorrect estimation of the distances required for targeted movements.
Ankle clonus
MedGen UID:
68672
Concept ID:
C0238651
Finding
Clonus is an involuntary tendon reflex that causes repeated flexion and extension of the foot. Ankle clonus is tested by rapidly flexing the foot upward.
Cerebellar degeneration
MedGen UID:
75496
Concept ID:
C0262404
Disease or Syndrome
Atrophy (wasting) of the cerebellum.
Difficulty walking
MedGen UID:
86319
Concept ID:
C0311394
Finding
We walk thousands of steps each day. We walk to do our daily activities, get around, and exercise. Having a problem with walking can make daily life more difficult. . The pattern of how you walk is called your gait. A variety of problems can cause an abnormal gait and lead to problems with walking. These include: . -Injuries, diseases, or abnormal development of the muscles or bones of your legs or feet. -Movement disorders such as Parkinson's disease. -Diseases such as arthritis or multiple sclerosis. -Vision or balance problems. Treatment of walking problems depends on the cause. Physical therapy, surgery, or mobility aids may help.
Knee clonus
MedGen UID:
488908
Concept ID:
C0520823
Finding
.Clonus is an involuntary tendon reflex that causes repeated flexion and extension of the foot. Knee clonus can be tested by rapidly pushing the patella towards the toes.
Upper limb spasticity
MedGen UID:
220882
Concept ID:
C1273957
Finding
Global developmental delay
MedGen UID:
351243
Concept ID:
C1864897
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.
Motor delay
MedGen UID:
892432
Concept ID:
C4020874
Finding
A type of Developmental delay characterized by a delay in acquiring motor skills.
Spastic paraparesis
MedGen UID:
52432
Concept ID:
C0037771
Sign or Symptom
Mild or moderate loss of motor function accompanied by spasticity in the lower extremities. This condition is a manifestation of CENTRAL NERVOUS SYSTEM DISEASES that cause injury to the motor cortex or descending motor pathways.
Spastic paraplegia
MedGen UID:
20882
Concept ID:
C0037772
Disease or Syndrome
Spasticity and weakness of the leg and hip muscles.
Spastic gait
MedGen UID:
115907
Concept ID:
C0231687
Finding
Difficulty walking
MedGen UID:
86319
Concept ID:
C0311394
Finding
We walk thousands of steps each day. We walk to do our daily activities, get around, and exercise. Having a problem with walking can make daily life more difficult. . The pattern of how you walk is called your gait. A variety of problems can cause an abnormal gait and lead to problems with walking. These include: . -Injuries, diseases, or abnormal development of the muscles or bones of your legs or feet. -Movement disorders such as Parkinson's disease. -Diseases such as arthritis or multiple sclerosis. -Vision or balance problems. Treatment of walking problems depends on the cause. Physical therapy, surgery, or mobility aids may help.
Monoparesis - leg
MedGen UID:
605376
Concept ID:
C0427068
Finding
Weakness of the muscles of the legs.
Camptodactyly
MedGen UID:
195780
Concept ID:
C0685409
Congenital Abnormality
The distal interphalangeal joint and/or the proximal interphalangeal joint of the fingers or toes cannot be extended to 180 degrees by either active or passive extension.
Upper limb spasticity
MedGen UID:
220882
Concept ID:
C1273957
Finding
Distal amyotrophy
MedGen UID:
338530
Concept ID:
C1848736
Disease or Syndrome
Muscular atrophy affecting muscles in the distal portions of the extremities.
Brachydactyly
MedGen UID:
67454
Concept ID:
C0221357
Congenital Abnormality
Digits that appear disproportionately short compared to the hand/foot. The word brachydactyly is used to describe a series of Mendelian diseases characterized by distinct patterns of shortened digits (brachydactyly types A-E). This is the sense used here, however, it is preferable to described the observed phenotypic abnormalities precisely.
Ankle clonus
MedGen UID:
68672
Concept ID:
C0238651
Finding
Clonus is an involuntary tendon reflex that causes repeated flexion and extension of the foot. Ankle clonus is tested by rapidly flexing the foot upward.
Clinodactyly
MedGen UID:
120550
Concept ID:
C0265610
Congenital Abnormality
An angulation of a digit at an interphalangeal joint in the plane of the palm (finger) or sole (toe).
Kyphoscoliosis
MedGen UID:
154361
Concept ID:
C0575158
Anatomical Abnormality
An abnormal curvature of the spine in both a coronal (lateral) and sagittal (back-to-front) plane.
Camptodactyly
MedGen UID:
195780
Concept ID:
C0685409
Congenital Abnormality
The distal interphalangeal joint and/or the proximal interphalangeal joint of the fingers or toes cannot be extended to 180 degrees by either active or passive extension.
Hammertoe
MedGen UID:
209712
Concept ID:
C1136179
Anatomical Abnormality
Hyperextension of the metatarsal-phalangeal joint with hyperflexion of the proximal interphalangeal (PIP) joint.
Short foot
MedGen UID:
376415
Concept ID:
C1848673
Finding
A measured foot length that is more than 2 SD below the mean for a newborn of 27 - 41 weeks gestation, or foot that is less than the 3rd centile for individuals from birth to 16 years of age (objective). Alternatively, a foot that appears disproportionately short (subjective).
Hyperextensible hand joints
MedGen UID:
347323
Concept ID:
C1856877
Finding
The ability of the joints of the hand to move beyond their normal range of motion.
Drooling
MedGen UID:
8484
Concept ID:
C0013132
Sign or Symptom
Habitual flow of saliva out of the mouth.
Hypertelorism
MedGen UID:
9373
Concept ID:
C0020534
Congenital Abnormality
Although hypertelorism means an excessive distance between any paired organs (e.g., the nipples), the use of the word has come to be confined to ocular hypertelorism. Hypertelorism occurs as an isolated feature and is also a feature of many syndromes, e.g., Opitz G syndrome (145410), Greig cephalopolysyndactyly (175700), and Noonan syndrome (163950) (summary by Cohen et al., 1995).
Hyperplasia of midface
MedGen UID:
481089
Concept ID:
C3279459
Finding
Abnormally anterior positioning of the infraorbital and perialar regions, or increased convexity of the face, or increased nasolabial angle. The midface includes the maxilla, the cheeks, the zygomas, and the infraorbital and perialar regions of the face
Camptodactyly
MedGen UID:
195780
Concept ID:
C0685409
Congenital Abnormality
The distal interphalangeal joint and/or the proximal interphalangeal joint of the fingers or toes cannot be extended to 180 degrees by either active or passive extension.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVTroyer syndrome
Follow this link to review classifications for Troyer syndrome in Orphanet.

Recent clinical studies

Etiology

Milewska M, Byrne PC
Cell Biol Int 2015 Sep;39(9):1007-15. Epub 2015 May 8 doi: 10.1002/cbin.10472. PMID: 25821002
Joshi DC, Bakowska JC
PLoS One 2011 Apr 29;6(4):e19290. doi: 10.1371/journal.pone.0019290. PMID: 21559443Free PMC Article
Lu J, Rashid F, Byrne PC
J Neurochem 2006 Sep;98(6):1908-19. doi: 10.1111/j.1471-4159.2006.04008.x. PMID: 16945107
Bakowska JC, Jenkins R, Pendleton J, Blackstone C
Biochem Biophys Res Commun 2005 Sep 9;334(4):1042-8. doi: 10.1016/j.bbrc.2005.06.201. PMID: 16036216
Auer-Grumbach M, Fazekas F, Radner H, Irmler A, Strasser-Fuchs S, Hartung HP
J Neurol 1999 Jul;246(7):556-61. PMID: 10463356

Diagnosis

Tawamie H, Wohlleber E, Uebe S, Schmäl C, Nöthen MM, Abou Jamra R
Mol Cell Probes 2015 Oct;29(5):315-8. Epub 2015 May 20 doi: 10.1016/j.mcp.2015.05.006. PMID: 26003402
Rainier S, Albers JW, Dyck PJ, Eldevik OP, Wilcock S, Richardson RJ, Fink JK
Muscle Nerve 2011 Jan;43(1):19-25. doi: 10.1002/mus.21777. PMID: 21171093
Bakowska JC, Wang H, Xin B, Sumner CJ, Blackstone C
Arch Neurol 2008 Apr;65(4):520-4. doi: 10.1001/archneur.65.4.520. PMID: 18413476

Prognosis

Bakowska JC, Wang H, Xin B, Sumner CJ, Blackstone C
Arch Neurol 2008 Apr;65(4):520-4. doi: 10.1001/archneur.65.4.520. PMID: 18413476

Clinical prediction guides

Milewska M, Byrne PC
Cell Biol Int 2015 Sep;39(9):1007-15. Epub 2015 May 8 doi: 10.1002/cbin.10472. PMID: 25821002
Manzini MC, Rajab A, Maynard TM, Mochida GH, Tan WH, Nasir R, Hill RS, Gleason D, Al Saffar M, Partlow JN, Barry BJ, Vernon M, LaMantia AS, Walsh CA
Ann Neurol 2010 Apr;67(4):516-25. doi: 10.1002/ana.21923. PMID: 20437587Free PMC Article
Bakowska JC, Wang H, Xin B, Sumner CJ, Blackstone C
Arch Neurol 2008 Apr;65(4):520-4. doi: 10.1001/archneur.65.4.520. PMID: 18413476
Lu J, Rashid F, Byrne PC
J Neurochem 2006 Sep;98(6):1908-19. doi: 10.1111/j.1471-4159.2006.04008.x. PMID: 16945107
Auer-Grumbach M, Fazekas F, Radner H, Irmler A, Strasser-Fuchs S, Hartung HP
J Neurol 1999 Jul;246(7):556-61. PMID: 10463356

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...
Support Center