Infantile-onset X-linked Spinal Muscular Atrophy

Description

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.

Clinical Features

Top most frequent phenotypes and symptoms related to Infantile-onset X-linked Spinal Muscular Atrophy

  • Seizures
  • Generalized hypotonia
  • Scoliosis
  • Micrognathia
  • Strabismus
  • Muscle weakness
  • Muscular hypotonia
  • Cryptorchidism
  • Ptosis
  • Cognitive impairment

And another 45 symptoms. If you need more information about this disease we can help you.

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Incidence and onset information

Not enough data available about incidence and published cases.
No data available about the known clinical features onset.

Alternative names

Infantile-onset X-linked Spinal Muscular Atrophy Is also known as smax2, amc, distal, x-linked, arthrogryposis, x-linked, type i, spinal muscular atrophy, infantile x-linked, x-linked spinal muscular atrophy type 2, spinal muscular atrophy, x-linked lethal infantile, spinal muscular atrophy with arthrogryposis, x-linked distal.

Researches and researchers

Currently, we don't have any information about doctors, researches or researchers related to this disease. Please contact us if you would like to appear here.


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Infantile-onset X-linked Spinal Muscular Atrophy Recommended genes panels

Panel Name, Specifity and genes Tested/covered
X-Linked Spinal Muscular Atrophy (XLSMA) - UBE1 DNA Sequencing Test.

By Athena Diagnostics Inc (United States).

UBA1
Specificity
100 %
Genes
50 %
Atypical Spinal Muscular Atrophy Advanced Sequencing Evaluation.

By Athena Diagnostics Inc (United States).

UBA1, VRK1, BICD2, TRPV4, DYNC1H1, HSPB8, GARS, HSPB1, HSPB3, IGHMBP2
Specificity
10 %
Genes
50 %
Neuromuscular Disorders Panel.

By Greenwood Genetic Center Diagnostic Laboratories Greenwood Genetic Center (United States).

RYR1, BIN1, SCN4A, SGCA, SGCB, SGCD, SGCE, SGCG, SLC25A4, SUCLA2, SUCLG1, TWNK, TCAP, TIA1, TK2, TNNI2, TNNT1, TPM2, TPM3, MYOT , (...)

View the complete list with 124 more genes
Specificity
1 %
Genes
50 %
Congenital Contractures Panel.

By Greenwood Genetic Center Diagnostic Laboratories Greenwood Genetic Center (United States).

SKI, SLC18A3, TNNI2, TNNT3, TPM2, TPM3, UBA1, ZMPSTE24, ACTA1, ADGRG6, SLC5A7, KLHL41, FKBP10, NEK9, NALCN, CHAT, CHRNA1, CHRNB1, CHRND, CHRNE , (...)

View the complete list with 37 more genes
Specificity
4 %
Genes
100 %
Spinal muscular atrophy, X-linked, infantile (SMAX2, sequence analysis of UBA1 gene).

By CGC Genetics (Portugal).

UBA1
Specificity
100 %
Genes
50 %
Spinal muscular atrophy (NGS panel for 21 genes).

By CGC Genetics (Portugal).

SCO2, UBA1, VAPB, VRK1, SLC5A7, CHCHD10, BSCL2, EXOSC8, BICD2, TRPV4, REEP1, DCTN1, FBXO38, PLEKHG5, DYNC1H1, HSPB8, GARS, DNAJB2, IGHMBP2, ASAH1 , (...)

View the complete list with 1 more genes
Specificity
5 %
Genes
50 %
Spinal muscular atrophy, X-linked infantile.

By Institute of Human Genetics Uniklinik RWTH Aachen (Germany).

UBA1
Specificity
100 %
Genes
50 %
Spinal Muscular Atrophy, X-Linked Infantile.

By MGZ Medical Genetics Center (Germany).

UBA1
Specificity
100 %
Genes
50 %

We have 35 more panels available in our App

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Sources and references

You can check the following sources for additional information.

ORPHANET OMIM MESH Rare Disease Symptoms Checker

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