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Disease Profile

Arthrogryposis multiplex congenita, distal, X-linked

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.
<1 / 1 000 000

< 331

US Estimated

< 514

Europe Estimated

Age of onset

Neonatal

ICD-10

G12.1

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

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Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

AMC, distal, X-linked

Categories

Congenital and Genetic Diseases; Nervous System Diseases

Summary

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.
orphanet

Orpha Number: 1145

Definition
X-linked distal arthrogryposis multiplex congenital (SMAX2) is a rare form of spinal muscular atrophy characterized by the neonatal onset of severe hypotonia, areflexia, profound weakness, multiple congenital contractures, facial dysmorphic features (myopathic face with open, tent-shaped mouth), cryptorchidism, and mild skeletal abnormalities (i.e. kyphosis, scoliosis), that is often preceded by polyhydramnios and reduced fetal movements in utero and followed by bone fractures shortly after birth. SMAX2 patients often have a limited life span, often succumbing to the disease within 2 years, as muscle weakness is progressive and chest muscle involvement eventually leads to ventilatory insufficiency and respiratory failure.

Visit the Orphanet disease page for more resources.

Symptoms

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Camptodactyly of finger
Permanent flexion of the finger
0100490
Gait disturbance
Abnormal gait
Abnormal walk
Impaired gait

[ more ]

0001288
Joint stiffness
Stiff joint
Stiff joints

[ more ]

0001387
30%-79% of people have these symptoms
Adducted thumb
Inward turned thumb
0001181
Bilateral single transverse palmar creases
0007598
Cognitive impairment
Abnormality of cognition
Cognitive abnormality
Cognitive defects
Cognitive deficits
Intellectual impairment
Mental impairment

[ more ]

0100543
Cryptorchidism
Undescended testes
Undescended testis

[ more ]

0000028
Dolichocephaly
Long, narrow head
Tall and narrow skull

[ more ]

0000268
Failure to thrive in infancy
Faltering weight in infancy
Weight faltering in infancy

[ more ]

0001531
Kyphosis
Hunched back
Round back

[ more ]

0002808
Long philtrum
0000343
Micrognathia
Little lower jaw
Small jaw
Small lower jaw

[ more ]

0000347
Muscular hypotonia
Low or weak muscle tone
0001252
Narrow chest
Low chest circumference
Narrow shoulders

[ more ]

0000774
Proximal placement of thumb
Attachment of thumb close to wrist
0009623
Scoliosis
0002650
Short neck
Decreased length of neck
0000470
Short nose
Decreased length of nose
Shortened nose

[ more ]

0003196
Wide nasal bridge
Broad nasal bridge
Broad nasal root
Broadened nasal bridge
Increased breadth of bridge of nose
Increased breadth of nasal bridge
Increased width of bridge of nose
Increased width of nasal bridge
Nasal bridge broad
Wide bridge of nose
Widened nasal bridge

[ more ]

0000431
5%-29% of people have these symptoms
Abnormal fingernail morphology
Abnormal fingernails
Abnormality of the fingernails

[ more ]

0001231
Hypoplasia of penis
Underdeveloped penis
0008736
Macrotia
Large ears
0000400
Open mouth
Gaped jawed appearance
Gaped mouthed appearance
Slack jawed appearance

[ more ]

0000194
Ptosis
Drooping upper eyelid
0000508
Seizure
0001250
Skin dimple
0010781
Strabismus
Cross-eyed
Squint
Squint eyes

[ more ]

0000486
Thickened nuchal skin fold
Thickened skin folds of neck
Thickened skin over the neck

[ more ]

0000474
Wide intermamillary distance
Wide-spaced nipples
Widely spaced nipples
Widely-spaced nipples

[ more ]

0006610
Percent of people who have these symptoms is not available through HPO
Abnormality of metabolism/homeostasis
Laboratory abnormality
Metabolism abnormality

[ more ]

0001939
Areflexia
Absent tendon reflexes
0001284
Arthrogryposis multiplex congenita
0002804
Decreased fetal movement
Less than 10 fetal movements in 12 hours
0001558
Degeneration of anterior horn cells
0002398
Facial palsy
Bell's palsy
0010628
Hypospadias
0000047
Inguinal hernia
0000023
Micropenis
Short penis
Small penis

[ more ]

0000054
Multiple joint contractures
0002828
Myopathic facies
0002058
Myopathy
Muscle tissue disease
0003198
Respiratory insufficiency
Respiratory impairment
0002093
Respiratory insufficiency due to muscle weakness
Decreased lung function due to weak breathing muscles
0002747
Severe muscular hypotonia
Severely decreased muscle tone
0006829
Spinal muscular atrophy
Spinal muscle degeneration
Spinal muscle wasting

[ more ]

0007269
Tongue fasciculations
Tongue twitching
Twitching of the tongue

[ more ]

0001308
X-linked recessive inheritance
0001419

Diagnosis

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Arthrogryposis multiplex congenita, distal, X-linked. Click on the link to view a sample search on this topic.