MSX1

Chr 4AD

msh homeobox 1

Also known as: ECTD3, HOX7, HYD1, STHAG1

This gene encodes a transcriptional repressor that regulates embryonic development, particularly controlling odontogenesis (tooth development), craniofacial formation including palatal shelf fusion, and nail plate formation. Mutations cause autosomal dominant disorders affecting teeth and orofacial structures, including selective tooth agenesis with or without orofacial clefts, Witkop syndrome (ectodermal dysplasia with nail dysplasia and tooth abnormalities), and isolated orofacial clefts. These conditions typically present at birth or become apparent during early childhood as teeth develop.

Summary from RefSeq, OMIM, UniProt
Research Assistant →

Primary Disease Associations & Inheritance

Ectodermal dysplasia 3, Witkop typeMIM #189500
AD
Orofacial cleft 5MIM #608874
AD
Tooth agenesis, selective, 1, with or without orofacial cleftMIM #106600
AD
UniProtNon-syndromic orofacial cleft 5
0
Active trials
46
Pubs (1 yr)
138
P/LP submissions
4%
P/LP missense
1.01
LOEUF
LOF
Mechanism· G2P
Clinical SummaryMSX1
🧬
Gene-Disease Validity (ClinGen)
tooth agenesis, selective, 1 · ADDefinitive

Definitive — sufficient evidence for diagnostic panels

2 total gene-disease associations curated

Population Constraint (gnomAD)
Constrained for loss-of-function variants (OE-LoF 0.32) despite low pLI — interpret in context.
📋
ClinVar Variants
133 unique Pathogenic / Likely Pathogenic· 98 VUS of 291 total submissions
📖
GeneReview available — MSX1
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
1.01LOEUF
pLI 0.165
Z-score 1.57
OE 0.32 (0.131.01)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
0.28Z-score
OE missense 0.94 (0.821.07)
158 obs / 168.1 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.32 (0.131.01)
00.351.4
Missense OE0.94 (0.821.07)
00.61.4
Synonymous OE1.21
01.21.6
LoF obs/exp: 2 / 6.2Missense obs/exp: 158 / 168.1Syn Z: -1.45
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
definitiveMSX1-related cleft lip with or without cleft palateLOFAD
DN
0.6550th %ile
GOF
0.3788th %ile
LOF
0.65top 25%

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

DNprediction above median · 1 literature citation
LOFprediction above median · 1 literature citation

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.

Literature Evidence

DNWe propose that the Arg31Pro missense mutation produces the phenotype of FTA via a dominant negative mechanism. Because this homeoprotein is expected to interact with other transcription factors 18·21 and binds DNA 18, Arg31Pro MSXI could functionally inactivate partner proteins as well as perturb PMID:8696335
LOFA nonsense mutation in MSX1 causes Witkop syndromePMID:11369996

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

291 submitted variants in ClinVar

Classification Summary

Pathogenic123
Likely Pathogenic10
VUS98
Likely Benign32
Benign20
Conflicting3
123
Pathogenic
10
Likely Pathogenic
98
VUS
32
Likely Benign
20
Benign
3
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
11
4
108
0
123
Likely Pathogenic
1
1
8
0
10
VUS
2
87
9
0
98
Likely Benign
0
11
3
18
32
Benign
0
4
14
2
20
Conflicting
3
Total1410714220286

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

View in ClinVar →

Protein Context — Lollipop Plot

MSX1 · protein map & ClinVar variants

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

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →
Clinical Literature
Open Research Assistant →
Key Publications
Landmark & review papers · by relevance
PubMed
Top 5 results · since 2015Search PubMed ↗