ATP8A2
Chr 13ARATPase phospholipid transporting 8A2
Also known as: ATP, ATPIB, CAMRQ4, IB, ML-1
ATP8A2 encodes a P4-ATPase flippase that translocates phospholipids (particularly phosphatidylserine) from the outer to inner membrane leaflet to maintain membrane asymmetry and support vesicle trafficking in neuronal cells. Mutations cause cerebellar ataxia, impaired intellectual development, and dysequilibrium syndrome 4 with autosomal recessive inheritance. The gene is highly constrained against loss-of-function variants and the protein is required for normal visual and auditory function as well as photoreceptor and inner ear spiral ganglion cell survival.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
More LoF-intolerant than ~75% of genes
Moderately missense-constrained (top ~2.5%)
Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.
The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
399 submitted variants in ClinVar
Classification Summary
Curated Variants Distribution
Classified variants from ClinVar · 5 ACMG categories
| Classification | LoF | Missense + Inframe | Non-coding | Synonymous | Total |
|---|---|---|---|---|---|
Pathogenic | 12 | 0 | 18 | 0 | 30 |
Likely Pathogenic | 20 | 3 | 3 | 0 | 26 |
VUS | 0 | 159 | 22 | 1 | 182 |
Likely Benign | 0 | 5 | 42 | 66 | 113 |
Benign | 0 | 1 | 21 | 8 | 30 |
Conflicting | — | 12 | |||
| Total | 32 | 168 | 106 | 75 | 393 |
LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly
View in ClinVar →Protein Context — Lollipop Plot
ATP8A2 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
No active trials found for this gene.
Search ClinicalTrials.gov →External Resources
Links to major genomics databases and tools