SMIM22

Chr 16

small integral membrane protein 22

Also known as: CASIMO1

SMIM22 encodes a protein that modulates lipid droplet formation through interaction with squalene epoxidase (SQLE) and regulates actin cytoskeleton organization. The gene is highly constrained against loss-of-function variants (pLI ~1.0), suggesting that mutations would likely cause severe developmental disorders, though specific disease associations have not yet been established. Based on the constraint metrics, pathogenic variants would most likely follow an autosomal dominant inheritance pattern.

ResearchSummary from RefSeq, UniProt
MultiplemechanismLOEUF 1.95
Clinical SummarySMIM22
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
27 unique Pathogenic / Likely Pathogenic· 11 VUS of 39 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.95LOEUF
pLI 0.000
Z-score -1.36
OE 1.90 (0.811.95)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.96Z-score
OE missense 1.42 (1.151.75)
60 obs / 42.4 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE1.90 (0.811.95)
00.351.4
Missense OE1.42 (1.151.75)
00.61.4
Synonymous OE1.39
01.21.6
LoF obs/exp: 5 / 2.6Missense obs/exp: 60 / 42.4Syn Z: -1.33
DN
0.76top 25%
GOF
0.80top 10%
LOF
0.2091th %ile

This gene has evidence for multiple mechanisms of pathogenicity (gain-of-function and dominant-negative). Both the Badonyi & Marsh prediction and the broader genomic evidence point to gain-of-function as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

GOFprediction above median
DNprediction above median

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

39 submitted variants in ClinVar

Classification Summary

Pathogenic27
VUS11
27
Pathogenic
11
VUS

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories· variant type breakdown unavailable

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
27
Likely Pathogenic
0
VUS
11
Likely Benign
0
Benign
0
Total38

Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

SMIM22 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →
Clinical Literature
Open Research Assistant →
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC