chr22-20982397-G-C

Variant summary

Our verdict is Uncertain significance. The variant received -1 ACMG points: 0P and 1B. BP4

This summary comes from the ClinGen Evidence Repository: The NM_006767.4:c.26G>C variant in LZTR1 is a missense variant predicted to cause substitution of glycine by alanine at amino acid 9 (p.Gly9Ala). The highest population minor allele frequency in gnomAD v2.1.1 is 0.0001954 (9/23990 alleles) in the South Asian population (PM2_Supporting, BS1, and BA1 are not met). The computational predictor REVEL gives a score of 0.093, which is below the threshold of 0.3, evidence that does not predict a damaging effect on LZTR1 function (BP4). In summary, this variant meets the criteria to be classified as uncertain significance for RASopathy based on the ACMG/AMP criteria applied, as specified by the ClinGen RASopathy VCEP: BP4. (ClinGen RASopathy VCEP specifications version 1.3; 12/3/2024) LINK:https://erepo.genome.network/evrepo/ui/classification/CA10118269/MONDO:0021060/094

Frequency

Genomes: 𝑓 0.000098 ( 1 hom., cov: 33)
Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

LZTR1
NM_006767.4 missense

Scores

2
16

Clinical Significance

Uncertain significance reviewed by expert panel U:7B:1

Conservation

PhyloP100: -0.175

Publications

7 publications found
Variant links:
Genes affected
LZTR1 (HGNC:6742): (leucine zipper like post translational regulator 1) This gene encodes a member of the BTB-kelch superfamily. Initially described as a putative transcriptional regulator based on weak homology to members of the basic leucine zipper-like family, the encoded protein subsequently has been shown to localize exclusively to the Golgi network where it may help stabilize the Gogli complex. Deletion of this gene may be associated with DiGeorge syndrome. [provided by RefSeq, Jul 2008]
LZTR1 Gene-Disease associations (from GenCC):
  • LZTR1-related schwannomatosis
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • Noonan syndrome 10
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
  • schwannomatosis
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • Noonan syndrome
    Inheritance: AR, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • Noonan syndrome 2
    Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, PanelApp Australia, Genomics England PanelApp
  • breast cancer
    Inheritance: AD Classification: MODERATE Submitted by: G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received -1 ACMG points.

BP4
For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006767.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
LZTR1
NM_006767.4
MANE Select
c.26G>Cp.Gly9Ala
missense
Exon 1 of 21NP_006758.2

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
LZTR1
ENST00000646124.2
MANE Select
c.26G>Cp.Gly9Ala
missense
Exon 1 of 21ENSP00000496779.1
LZTR1
ENST00000700578.1
c.26G>Cp.Gly9Ala
missense
Exon 1 of 20ENSP00000515073.1
LZTR1
ENST00000645935.1
c.26G>Cp.Gly9Ala
missense
Exon 1 of 4ENSP00000493479.1

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152250
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000620
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.0000979
AC:
16
AN:
163374
AF XY:
0.000148
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000823
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000942
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000108
AC:
152
AN:
1408454
Hom.:
0
Cov.:
32
AF XY:
0.000128
AC XY:
89
AN XY:
695686
show subpopulations
African (AFR)
AF:
0.0000310
AC:
1
AN:
32304
American (AMR)
AF:
0.0000542
AC:
2
AN:
36880
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25246
East Asian (EAS)
AF:
0.0000271
AC:
1
AN:
36846
South Asian (SAS)
AF:
0.000360
AC:
29
AN:
80504
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
48640
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5694
European-Non Finnish (NFE)
AF:
0.000106
AC:
115
AN:
1084004
Other (OTH)
AF:
0.0000686
AC:
4
AN:
58336
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.486
Heterozygous variant carriers
0
9
18
26
35
44
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000984
AC:
15
AN:
152368
Hom.:
1
Cov.:
33
AF XY:
0.000107
AC XY:
8
AN XY:
74512
show subpopulations
African (AFR)
AF:
0.0000240
AC:
1
AN:
41590
American (AMR)
AF:
0.000196
AC:
3
AN:
15314
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.000828
AC:
4
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
292
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68032
Other (OTH)
AF:
0.000473
AC:
1
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.486
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000982
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000519
AC:
2
ExAC
AF:
0.0000602
AC:
7

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:7Benign:1
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

not provided Uncertain:2
Feb 20, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge

Jan 26, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 9 of the LZTR1 protein (p.Gly9Ala). This variant is present in population databases (rs756485244, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with LZTR1-related conditions. ClinVar contains an entry for this variant (Variation ID: 522164). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt LZTR1 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.

not specified Uncertain:1Benign:1
May 04, 2022
Mendelics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Mar 31, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: LZTR1 c.26G>C (p.Gly9Ala) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 9.8e-05 in 163374 control chromosomes. Although present at a frequency higher than estimated for Autosomal Dominant Noonan Syndrome And Related Conditions, this frequency is not significantly higher than estimated for a pathogenic variant in LZTR1 causing Autosomal Recessive Noonan Syndrome 2 (9.8e-05 vs 0.0032), allowing no conclusion about variant significance. To our knowledge, no occurrence of c.26G>C in individuals affected with Noonan Syndrome 2 and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 522164). Based on the evidence outlined above, the variant was classified as uncertain significance.

Noonan syndrome 10 Uncertain:1
Aug 10, 2022
St. Jude Molecular Pathology, St. Jude Children's Research Hospital
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The LZTR1 c.26G>C (p.Gly9Ala) missense change has a maximum subpopulation frequency of 0.038% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org/). The in silico tool REVEL predicts a benign effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. To our knowledge, this variant has not been reported in individuals with Noonan syndrome or Schwannomatosis. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance.

LZTR1-related schwannomatosis Uncertain:1
Feb 11, 2024
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Uncertain:1
Oct 27, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.G9A variant (also known as c.26G>C), located in coding exon 1 of the LZTR1 gene, results from a G to C substitution at nucleotide position 26. The glycine at codon 9 is replaced by alanine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

RASopathy Uncertain:1
Dec 03, 2024
ClinGen RASopathy Variant Curation Expert Panel
Significance:Uncertain significance
Review Status:reviewed by expert panel
Collection Method:curation

The NM_006767.4:c.26G>C variant in LZTR1 is a missense variant predicted to cause substitution of glycine by alanine at amino acid 9 (p.Gly9Ala). The highest population minor allele frequency in gnomAD v2.1.1 is 0.0001954 (9/23990 alleles) in the South Asian population (PM2_Supporting, BS1, and BA1 are not met). The computational predictor REVEL gives a score of 0.093, which is below the threshold of 0.3, evidence that does not predict a damaging effect on LZTR1 function (BP4). In summary, this variant meets the criteria to be classified as uncertain significance for RASopathy based on the ACMG/AMP criteria applied, as specified by the ClinGen RASopathy VCEP: BP4. (ClinGen RASopathy VCEP specifications version 1.3; 12/3/2024)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.096
BayesDel_addAF
Benign
-0.53
T
BayesDel_noAF
Benign
-0.69
CADD
Benign
13
DANN
Uncertain
0.98
DEOGEN2
Benign
0.024
T
Eigen
Benign
-0.83
Eigen_PC
Benign
-0.80
FATHMM_MKL
Benign
0.10
N
LIST_S2
Benign
0.66
T
M_CAP
Benign
0.053
D
MetaRNN
Benign
0.045
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.69
N
PhyloP100
-0.17
PrimateAI
Uncertain
0.60
T
PROVEAN
Benign
-0.32
N
REVEL
Benign
0.093
Sift
Benign
0.25
T
Sift4G
Benign
0.34
T
Polyphen
0.0
B
Vest4
0.084
MutPred
0.38
Gain of helix (P = 0.0496)
MVP
0.055
MPC
1.5
ClinPred
0.11
T
GERP RS
-0.98
PromoterAI
-0.0024
Neutral
RBP_binding_hub_radar
0.92
RBP_regulation_power_radar
3.1
Varity_R
0.064
gMVP
0.74
Mutation Taster
=96/4
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs756485244; hg19: chr22-21336686; API