LZTR1

Chr 22ADAR

leucine zipper like post translational regulator 1

Also known as: BTBD29, LZTR-1, NS10, NS2, SWNTS2

The protein functions as a substrate-specific adapter of an E3 ubiquitin ligase complex that targets Ras proteins for degradation, acting as a negative regulator of RAS-MAPK signaling by controlling Ras levels and membrane association. Mutations cause Noonan syndrome (types 2 and 10) and predispose to schwannomatosis-2, following both autosomal dominant and autosomal recessive inheritance patterns. The gene shows extremely high constraint against loss-of-function variants, indicating that such mutations are typically not tolerated.

OMIMResearchSummary from RefSeq, OMIM, UniProt
LOFmechanismAD/ARLOEUF 1.993 OMIM phenotypes
VCEP Guidelines: RASopathyReleased
View SpecificationsClinGen Panel
Clinical SummaryLZTR1
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Gene-Disease Validity (ClinGen)
Noonan syndrome · ADDefinitive

Definitive — sufficient evidence for diagnostic panels

2 total gene-disease associations curated

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
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ClinVar Variants
92 unique Pathogenic / Likely Pathogenic· 266 VUS of 500 total submissions
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Clinical Trials
1 active or recruiting trial — potential therapeutic options may be available

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.99LOEUF
pLI 0.000
Z-score -8.05
OE 2.28 (1.751.99)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
0.58Z-score
OE missense 0.93 (0.861.00)
503 obs / 540.7 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE2.28 (1.751.99)
00.351.4
Missense OE0.93 (0.861.00)
00.61.4
Synonymous OE1.07
01.21.6
LoF obs/exp: 105 / 46.0Missense obs/exp: 503 / 540.7Syn Z: -0.91
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
definitiveLZTR1-related Noonan syndrome (monoallelic)OTHERAD
strongLZTR1-related Noonan syndrome (biallelic)OTHERAR
moderateLZTR1-related breast cancer, susceptibility toOTHERAD
definitiveLZTR1-related schwannomatosisLOFAD
DN
0.6163th %ile
GOF
0.6247th %ile
LOF
0.48top 25%

The Badonyi & Marsh model scores gain-of-function highest, but genomic evidence most strongly supports loss-of-function (haploinsufficiency) as the primary mechanism.

LOF1 literature citation · 85% of P/LP variants are LoF

Literature Evidence

LOFWe found that Lztr1 haploinsufficiency in mice recapitulates Noonan syndrome phenotypes, whereas LZTR1 loss in Schwann cells drives dedifferentiation and proliferation.PMID:30442762

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312. Mechanism ranking also informed by gnomAD constraint, ClinVar, and ClinGen data.

ClinVar Variant Classifications

500 submitted variants in ClinVar

Classification Summary

Pathogenic75
Likely Pathogenic17
VUS266
Likely Benign124
Conflicting3
75
Pathogenic
17
Likely Pathogenic
266
VUS
124
Likely Benign
3
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
64
0
11
0
75
Likely Pathogenic
14
2
1
0
17
VUS
9
207
46
4
266
Likely Benign
0
0
62
62
124
Benign
0
0
0
0
0
Conflicting
3
Total8720912066485

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

View in ClinVar →

Protein Context — Lollipop Plot

LZTR1 · protein map & ClinVar variants

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

3D Protein StructureAlphaFold
Clinical Literature
Open Research Assistant →
Key Publications
Landmark & review papers · by relevance
PubMed
Top 5 results · since 2015Search PubMed ↗