Categories: Vision / eye phene , Nervous system phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 600415 (gene) , 277460 (trait)

Links to relevant human diseases in MONDO:

• MONDO:0010188: familial isolated deficiency of vitamin E

Single-gene trait/disorder: yes

Mode of inheritance: Autosomal recessive

Disease-related: yes

Key variant known: yes

Year key variant first reported: 2025

Species-specific name: Retinopathy with Vitamin E deficiency; central progressive retinal atrophy; vitamin E deficiency retinopathy; retinal pigment epithelial dystrophy

Species-specific symbol: RVED

Mapping: Oliver et al. (2005) conducted a genome-wide association study in English Cocker Spaniels and identified a statistically associated signal on chromosome 29.

Molecular basis: Oliver et al. (2025): "Whole genome sequencing (WGS) of two [English Cocker Spaniel] cases identified a 102bp deletion in exon 1 of the Alpha Tocopherol Transfer Protein gene (TTPA), truncating the protein by 34 amino acids. The c.23_124del variant segregated with RVED in a total of 30 cases and 43 controls."

Clinical features: Oliver et al. (2024): "Ophthalmic abnormalities observed in [Retinopathy with Vitamin E Deficiency]-affected [English Cocker Spaniel] include lipofuscin granule deposition within the tapetal fundus and subsequent retinal degeneration resulting in visual deficits. Affected dogs may also exhibit neurological signs that include ataxia and hindlimb proprioceptive deficit. In all cases, circulating plasma concentrations of alpha-tocopherol are low."

Breed: English Cocker Spaniel (Dog) (VBO_0200486).
Breeds in which the phene has been documented. (If a likely causal variant has been documented for the phene, see the variant table breeds in which the variant has been reported).

Associated gene: