raremaprare-disease reference indexOrphadata 2026-06-23 · HPO 2026-09-01
ORPHA:404521

Spinal muscular atrophy with respiratory distress type 2

Synonyms: Diaphragmatic spinal muscular atrophy type 2 · SMARD2 · Severe infantile axonal neuropathy with respiratory failure type 2 · X-linked spinal muscular atrophy with respiratory distress

Type
Disease
Group
Disorder
Inheritance
Unknown
Age of onset
Neonatal
Status
active

Spinal muscular atrophy with respiratory distress type 2 is a rare, genetic, motor neuron disease characterized by progressive early respiratory failure associated with diaphragm paralysis, distal muscular weakness, joint contractures, and axial hypotonia with preserved antigravity limb movements. Phenotype overlaps considerably with SMARD type 1 but is differentiated by a mutation in a different gene.

1

Names in Orphadata languages

12 of 12 languages
LangNameSynonyms
enSpinal muscular atrophy with respiratory distress type 2Diaphragmatic spinal muscular atrophy type 2 · SMARD2 · Severe infantile axonal neuropathy with respiratory failure type 2 · X-linked spinal muscular atrophy with respiratory distress
frAmyotrophie spinale avec détresse respiratoire type 2Amyotrophie spinale diaphragmatique type 2 · Amyotrophie spinale liée à l'X avec détresse respiratoire · Neuropathie axonale infantile sévère avec insuffisance respiratoire type 2 · SMARD2
deSpinale Muskelatrophie mit Atemnot Typ 2SMARD2 · Schwere infantile axonale Neuropathie mit Atemversagen Typ 2 · Spinale Muskelatrophie, diaphragmatische, Typ 2 · X-chromosomale spinale Muskelatrophie mit Atemnot
esAtrofia muscular espinal con insuficiencia respiratoria tipo 2Atrofia muscular espinal diafragmática tipo 2 · Atrofia muscular espinal ligada al cromosoma X con insuficiencia respiratoria · Neuropatía axonal infantil grave con insuficiencia respiratoria tipo 2 · SMARD2
itAtrofia muscolare spinale con distress respiratorio, tipo 2Atrofia muscolare diaframmatica, tipo 2 · Atrofia muscolare legata all'X con distress respiratorio · Neuropatia assonale infantile grave con insufficienza respiratoria, tipo 2 · SMARD2
nlSpinale spieratrofie met ademhalingsnood type 2Diafragmatische spinale spieratrofie type 2 · Ernstige infantiele axonale neuropathie met respiratoir falen type 2 · SMARD2 · X-gebonden spinale musculaire atrofie met respiratoire insufficiëntie
ptAtrofia muscular espinhal com dificuldade respiratória tipo 2
plRdzeniowy zanik mięśni z niewydolnością oddechową typu 2Ciężka dziecięca neuropatia aksonalna z niewydolnością oddechową typu 2 · Rdzeniowy zanik mięśni przepony typu 2 · Rdzeniowy zanik mięśni z niewydolnością oddechową sprzężony z chromosomem X · SMARD2
csSpinální muskulární atrofie s respirační tísní, typ 2Diafragmatická spinální muskulární atrofie, typ 2 · SMARD2 · Těžká infantilní axonální neuropatie s respiračním selháním, typ 2 · X-vázaná spinální svalová atrofie s respirační tísní
ukСпінальна мязова атрофія з респіраторним дистрес-синдромом, тип 2Діафрагмальна спінальна мязова атрофія, тип 2 · Тяжка дитяча аксональна нейропатія з дихальною недостатністю 2 типу · SMARD2 · Х-зчеплена спінальна мязова атрофія з дихальними розладами
zh脊髓性肌萎缩伴呼吸窘迫2型严重的小儿轴索神经病伴呼吸衰竭2型
trSolunum sıkıntısı tip 2 ile seyreden spinal müsküler atrofiSMARD2 · Diyafragmatik spinal kas atrofisi tip 2 · Solunum sıkıntısı ile seyretmeyen X'e bağlı spinal müsküler atrofi · Solunum yetmezliği tip 2 ile seyretmeyen ağır infantil aksonal nöropati

Definition in:

2

Cross-references

qualifier = Orphanet mapping relation
SourceCodeQualifierICD relationValidation
ICD-10G12.2NTBTattributedvalidated
MONDO0018450Evalidated
UMLSC4749434Evalidated

E exact · NTBT this ORPHAcode is narrower than the target · BTNT broader than the target · ND not decided.

3

Classification

Preferential parent (Orphanet linearisation):

Parents in the classifications (1):

No children.

4

Genes

1 direct
GeneAssociationStatusHGNCEnsemblOMIMLocusNameSource of validation
LAS1LDisease-causing germline mutation(s) inAssessedHGNC:25726ENSG00000001497300964Xq12LAS1 like ribosome biogenesis factor24647030[PMID]
5

Prevalence and incidence

2 records
TypeClassValueAreaQualificationValidationSource
Cases/families1 casesWorldwideCase(s)Validated24647030[PMID]
Point prevalence<1 / 1 000 000—WorldwideClass onlyValidatedORPHANET_24647030[PMID]

Value is Orphadata's ValMoy: the mean estimate per 100 000 for prevalence and incidence, the number of cases or families for case reports.

6

HPO phenotypes

Orphanet has no HPO annotation for this code in this release.

7

Sources for this card