ST8SIA2
Chr 15ST8 alpha-N-acetyl-neuraminide alpha-2,8-sialyltransferase 2
Also known as: HsT19690, SIAT8-B, SIAT8B, ST8SIA-II, ST8SiaII, STX
The enzyme catalyzes the transfer of sialic acid to produce polysialic acid on neural cell adhesion molecule (NCAM1) and other glycoproteins, supporting neurite outgrowth and influencing oligodendrocyte differentiation and myelin integrity. Mutations cause autosomal recessive intellectual disability with seizures and language delay, affecting neurodevelopment in early childhood. The gene shows moderate constraint against loss-of-function variants (LOEUF 0.651), consistent with its role in critical neurodevelopmental processes.
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Typical tolerance to LoF variation
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
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
ST8SIA2 · 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