Ataxia
Gene: AIFM1
AIFM1 encodes a mitochondrial flavoprotein required for NADH oxidation and caspase‑independent apoptosis. Pathogenic variants cause a spectrum of X‑linked neuro‑developmental and mitochondrial disorders that frequently feature cerebellar ataxia.
**X‑linked hypomyelination with spondylometaphyseal dysplasia (H‑SMD)** – six unrelated families (12 patients) with loss‑of‑function AIFM1 variants present with hypomyelination, spondylometaphyseal dysplasia, ataxia and additional neurologic signs (PMID 28842795).
**Severe X‑linked mitochondrial encephalomyopathy** – two families (two patients) with loss‑of‑function missense variants display cerebellar ataxia, peripheral neuropathy, hearing loss, optic atrophy and muscle weakness (PMID 37603145; PMID 25934856).
**X‑linked hereditary sensory and autonomic neuropathy with hearing loss** – three independent families (12 patients) harbor distinct missense AIFM1 variants and share cerebellar ataxia, peripheral neuropathy, sensorineural hearing loss and colour‑vision deficiency (PMID 31523922; PMID 32337346; PMID 39601015).
** Charcot-Marie-Tooth disease X‑linked recessive 4** – one family (four patients) with a gain‑of‑function missense variant shows hearing loss, peripheral neuropathy, distal muscle wasting and ataxic gait (PMID 31188924).
Sources: LiteratureCreated: 5 Sep 2026, 9:18 p.m.
Mode of inheritance
X-LINKED: hemizygous mutation in males, biallelic mutations in females
Phenotypes
Charcot-Marie-Tooth disease X-linked recessive 4, MONDO:0010689; X-linked hereditary sensory and autonomic neuropathy with hearing loss, MONDO:0010378; severe X-linked mitochondrial encephalomyopathy, MONDO:0010437; spondyloepimetaphyseal dysplasia, Bieganski type, MONDO:0010275
Publications
Gene: aifm1 has been classified as Green List (High Evidence).
Gene: aifm1 has been classified as Green List (High Evidence).
gene: AIFM1 was added gene: AIFM1 was added to Ataxia. Sources: Literature Mode of inheritance for gene: AIFM1 was set to X-LINKED: hemizygous mutation in males, biallelic mutations in females Publications for gene: AIFM1 were set to 39601015; 37603145; 32337346; 31523922; 31188924; 28842795; 25934856 Phenotypes for gene: AIFM1 were set to Charcot-Marie-Tooth disease X-linked recessive 4, MONDO:0010689; X-linked hereditary sensory and autonomic neuropathy with hearing loss, MONDO:0010378; severe X-linked mitochondrial encephalomyopathy, MONDO:0010437; spondyloepimetaphyseal dysplasia, Bieganski type, MONDO:0010275 Review for gene: AIFM1 was set to GREEN