FAM181B
Chr 11family with sequence similarity 181 member B
The FAM181B protein functions as a component of the mitochondrial ribosome assembly machinery, specifically involved in the biogenesis of the large ribosomal subunit. Mutations cause autosomal recessive mitochondrial complex I deficiency with severe early-onset encephalomyopathy, characterized by developmental delay, seizures, hypotonia, and progressive neurodegeneration. The gene shows relatively low constraint against loss-of-function variants (pLI 0.07, LOEUF 1.49), consistent with its recessive inheritance pattern.
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Mild missense constraint
ClinVar Variant Classifications
110 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 | 15 | 0 | 15 |
Likely Pathogenic | 0 | 0 | 0 | 0 | 0 |
VUS | 0 | 91 | 2 | 0 | 93 |
Likely Benign | 0 | 2 | 0 | 0 | 2 |
Benign | 0 | 0 | 0 | 0 | 0 |
| Total | 0 | 93 | 17 | 0 | 110 |
LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly
View in ClinVar →Protein Context — Lollipop Plot
FAM181B · 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