rs587777179

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_006767.4(LZTR1):​c.2348_2351delCGCA​(p.Thr783ArgfsTer5) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,612,410 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. T783T) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

LZTR1
NM_006767.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 9.03

Publications

1 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: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 22-20996906-AACGC-A is Pathogenic according to our data. Variant chr22-20996906-AACGC-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 101037.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
LZTR1NM_006767.4 linkc.2348_2351delCGCA p.Thr783ArgfsTer5 frameshift_variant Exon 20 of 21 ENST00000646124.2 NP_006758.2 Q8N653A0A384NL67

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
LZTR1ENST00000646124.2 linkc.2348_2351delCGCA p.Thr783ArgfsTer5 frameshift_variant Exon 20 of 21 NM_006767.4 ENSP00000496779.1 Q8N653

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152230
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460180
Hom.:
0
AF XY:
0.00000138
AC XY:
1
AN XY:
726176
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33456
American (AMR)
AF:
0.00
AC:
0
AN:
44672
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26080
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39652
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86222
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53004
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1111004
Other (OTH)
AF:
0.00
AC:
0
AN:
60322
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152230
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74372
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41468
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.325
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000189

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

LZTR1-related schwannomatosis Pathogenic:1
Feb 01, 2014
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

not provided Pathogenic:1
Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Thr783Argfs*5) in the LZTR1 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 58 amino acid(s) of the LZTR1 protein. This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with clinical features of schwannomatosis (PMID: 24362817). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 101037). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. This variant disrupts a region of the LZTR1 protein in which other variant(s) (p.Ile821Thr, p.Cys792Gly, p.Asp819His) have been observed in individuals with LZTR1-related conditions (PMID: 29469822, 30732632, 31219622). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Pathogenic:1
Nov 21, 2024
Ambry Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.2348_2351delCGCA variant, located in coding exon 20 of the LZTR1 gene, results from a deletion of 4 nucleotides at nucleotide positions 2348 to 2351, causing a translational frameshift with a predicted alternate stop codon (p.T783Rfs*5). This alteration occurs at the 3' terminus of the LZTR1 gene, is not expected to trigger nonsense-mediated mRNAdecay, and only impacts the last 58 amino acids of the protein. However, premature stop codons are typically deleterious in nature, the impacted region is critical for protein function, and a significant portion of the protein is affected (Ambry internal data). This variant has been identified in one individual with schwannomatosis and segregated with disease in two affected family members; analysis of a schwannoma was also consistent with the known mechanism of tumorigenesis (Piotrowski A et al. Nat Genet, 2014 Feb;46:182-7). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the supporting evidence, this variant is likely pathogenic for an increased risk of LZTR1-related schwannomatosis (SWN) and would be expected to cause autosomal recessive Noonan syndrome when present along with a second pathogenic or likely pathogenic variant on the other allele; however, the association of this alteration with autosomal dominant Noonan syndrome is unlikely. -

Noonan syndrome 2 Pathogenic:1
Jul 19, 2022
Pittsburgh Clinical Genomics Laboratory, University of Pittsburgh Medical Center
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence variant is a deletion of 4 nucleotides (delCGCA) from coding nucleotide positions 2348 through 2351 in the LZTR1 gene which results in an early termition codon 5 positions downstream of the frameshift introduced at codon 783. As it occurs in exon 20 of 21, this variant is predicted to generate a non-functiol allele through either the expression of a truncated protein or a loss of LZTR1 expression due to nonsense-mediated decay. This is a previously reported variant (ClinVar) which has been observed in the literature in multiple family members with schwannomatosis (PMID: 24362817). This variant is absent from the gnomAD control population dataset (0/~250000 alleles). Based on the available evidence, we consider this variant to be pathogenic. ACMG Criteria: PM2, PP1, PVS1 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
9.0
Mutation Taster
=1/199
disease causing (ClinVar)

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: rs587777179; hg19: chr22-21351195; API