X-linked distal spinal muscular atrophy…

Caring for someone with this diagnosis? Eleplan keeps diagnoses, medications, documents and every specialist in one plan.

Start free with Eleplan

X-linked distal spinal muscular atrophy type 3

ORPHA:139557Disease

Also called ATP7A-related distal motor neuropathy · DSMAX · SMAX3 · X-linked dHMN3 · X-linked dSMA3 · X-linked distal hereditary motor neuropathy type 3

What it is

X-linked distal spinal muscular atrophy type 3 is a rare distal hereditary motor neuropathy characterized by slowly progressive atrophy and weakness of distal muscles of hands and feet with normal deep tendon reflexes or absent ankle reflexes and minimal or no sensory loss, sometimes mild proximal weakness in the legs and feet and hand deformities in males.

Key facts

Prevalence
<1 / 1 000 000
Age of onset
Adolescent, Adult, Childhood, Infancy
Inheritance
X-linked recessive
Classified as
Disease

Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.

Gene

ATP7ADisease-causing germline mutation(s)

ICD-10 codes

G12.1filed under a broader ICD-10 category — shared with 15 other rare diseases

ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.

Related health topics

Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.

Benefit programs to look at

Programs whose eligibility touches the same ICD-10 categories. Eligibility is decided by the administering agency, never by this page.

Cross-references

MESH C564506MONDO 10338OMIM 300489UMLS C1845359

Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.

Powered by Eleplan

A rare diagnosis is just the start. Eleplan keeps the whole care plan in one place.

Diagnoses, medications, documents, appointments, and the whole care team — organized and always in sync, so you are not retelling the same story to every new specialist. With Ellie, your AI care assistant, on top of it. Free to start.