SKA1
Chr 18spindle and kinetochore associated complex subunit 1
Also known as: C18orf24
The SKA1 protein is a component of the SKA complex that stabilizes spindle microtubule-kinetochore attachments during cell division and assists in chromosome alignment at the mitotic spindle equator. Biallelic mutations cause microcephaly with early-onset seizures and developmental delay, following autosomal recessive inheritance. This gene is highly intolerant to loss-of-function variants in the general population, suggesting that complete loss of protein function is likely incompatible with normal development.
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Mild missense constraint
The highest-scoring mechanism for this gene is dominant-negative.
Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
75 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 | 0 | 0 | 40 | 0 | 40 |
Likely Pathogenic | 0 | 0 | 1 | 0 | 1 |
VUS | 0 | 19 | 4 | 0 | 23 |
Likely Benign | 0 | 3 | 0 | 0 | 3 |
Benign | 0 | 0 | 0 | 0 | 0 |
| Total | 0 | 22 | 45 | 0 | 67 |
LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly
View in ClinVar →Protein Context — Lollipop Plot
SKA1 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
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