ALG12

Chr 22AR

ALG12 alpha-1,6-mannosyltransferase

Also known as: CDG1G, ECM39, PP14673, hALG12

This protein catalyzes the addition of the eighth mannose residue in an alpha-1,6 linkage onto the dolichol-PP-oligosaccharide precursor required for N-linked protein glycosylation. Mutations cause congenital disorder of glycosylation type Ig (CDG-Ig) through autosomal recessive inheritance, resulting in abnormal N-glycosylation due to loss of enzyme function.

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt, Mechanism
LOFmechanismARLOEUF 1.031 OMIM phenotype
Clinical SummaryALG12
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Gene-Disease Validity (ClinGen)
ALG12-congenital disorder of glycosylation · ARDefinitive

Definitive — sufficient evidence for diagnostic panels

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
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ClinVar Variants
16 unique Pathogenic / Likely Pathogenic· 24 VUS of 100 total submissions
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GeneReview available — ALG12
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.03LOEUF
pLI 0.000
Z-score 1.45
OE 0.66 (0.431.03)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.19Z-score
OE missense 1.03 (0.941.14)
295 obs / 285.8 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.66 (0.431.03)
00.351.4
Missense OE1.03 (0.941.14)
00.61.4
Synonymous OE1.20
01.21.6
LoF obs/exp: 14 / 21.2Missense obs/exp: 295 / 285.8Syn Z: -1.87
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
definitiveALG12-related congenital disorder of glycosylationLOFAR

Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.

DN
0.6745th %ile
GOF
0.6052th %ile
LOF
0.2969th %ile

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

100 submitted variants in ClinVar

Classification Summary

Pathogenic15
Likely Pathogenic1
VUS24
Likely Benign59
Benign1
15
Pathogenic
1
Likely Pathogenic
24
VUS
59
Likely Benign
1
Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
4
0
11
0
15
Likely Pathogenic
1
0
0
0
1
VUS
0
23
1
0
24
Likely Benign
0
2
15
42
59
Benign
0
1
0
0
1
Total5262742100

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

ALG12 · 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