Categories: Nervous system phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 103270 (gene) , 620887 (trait)

Single-gene trait/disorder: yes

Mode of inheritance: Probably autosomal recessive

Disease-related: yes

Key variant known: yes

Year key variant first reported: 2025

Key variant is published: no

Species summary: Willis et al. (2024) report a novel lethal spinocerebellar ataxia in 12 related young Quarter Horses "that is etiologically distinct from other clinically similar neurological disorders."

Species-specific name: Equine Juvenile Spinocerebellar Ataxia; EJSCA

Molecular basis: Brown et al. (2025) report in a conference abstract reduced FDXR expression in horses with equine juvenile spinocerebellar ataxia and propose that an intronic G>C SNP in intron 2 of FDXR is the likely causal variant. The variant introduces a new splice site,  resulting in a cryptic exon which is predicted to result in nonsense-mediated mRNA decay. Details of the postition of the variant are not provided in the abstract.

Breed: Quarter Horse (Horse) (VBO_0001057).
Breeds in which the phene or likely causal variants have been documented. If a likely causal variant has been documented, see variant-specific breed information in the variant table. (Breed information may be incomplete).

Associated gene: