16-2088267-A-G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2PP3

The NM_000548.5(TSC2):​c.5201A>G​(p.Asp1734Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,612,986 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D1734E) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 34)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

7
8
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 9.07

Publications

3 publications found
Variant links:
Genes affected
TSC2 (HGNC:12363): (TSC complex subunit 2) This gene is a tumor suppressor gene that encodes the growth inhibitory protein tuberin. Tuberin interacts with hamartin to form the TSC protein complex which functions in the control of cell growth. This TSC protein complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]
TSC2 Gene-Disease associations (from GenCC):
  • tuberous sclerosis
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • tuberous sclerosis 2
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, Ambry Genetics
  • lymphangioleiomyomatosis
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • tuberous sclerosis complex
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.814

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC2NM_000548.5 linkc.5201A>G p.Asp1734Gly missense_variant Exon 41 of 42 ENST00000219476.9 NP_000539.2 P49815-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TSC2ENST00000219476.9 linkc.5201A>G p.Asp1734Gly missense_variant Exon 41 of 42 5 NM_000548.5 ENSP00000219476.3 P49815-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152180
Hom.:
0
Cov.:
34
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:
0.00000137
AC:
2
AN:
1460806
Hom.:
0
Cov.:
35
AF XY:
0.00000138
AC XY:
1
AN XY:
726670
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52360
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111998
Other (OTH)
AF:
0.00
AC:
0
AN:
60382
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

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152180
Hom.:
0
Cov.:
34
AF XY:
0.00
AC XY:
0
AN XY:
74340
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68016
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:1
Sep 04, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 1734 of the TSC2 protein (p.Asp1734Gly). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TSC2-related conditions. ClinVar contains an entry for this variant (Variation ID: 405986). 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 TSC2 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 provided Uncertain:1
Aug 23, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Observed in conjunction with another TSC2 variant in an individual with cortical dysplasia or epilepsy (PMID: 32917966); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); De novo variant with confirmed parentage in a patient referred for genetic testing at GeneDx; however, the reported clinical features are only partially consistent with the features typically observed in individuals with pathogenic variants in this gene; This variant is associated with the following publications: (PMID: 32917966) -

Hereditary cancer-predisposing syndrome Uncertain:1
Apr 03, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.D1734G variant (also known as c.5201A>G), located in coding exon 40 of the TSC2 gene, results from an A to G substitution at nucleotide position 5201. The aspartic acid at codon 1734 is replaced by glycine, an amino acid with similar properties. This alteration was identified in 1 of 374 patients with clinically suspected TSC undergoing genetic testing within the TSC1 and TSC2 genes (Meng Y et al. J Hum Genet, 2021 Mar;66:227-236). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.65
BayesDel_addAF
Pathogenic
0.32
D
BayesDel_noAF
Pathogenic
0.23
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.82
D;.;.;.;.;.;.;.;.;.;.;.;D;.;D
Eigen
Uncertain
0.27
Eigen_PC
Uncertain
0.31
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.95
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.62
D
MetaRNN
Pathogenic
0.81
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.48
D
MutationAssessor
Benign
0.15
N;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100
9.1
PrimateAI
Uncertain
0.74
T
PROVEAN
Uncertain
-3.5
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
REVEL
Pathogenic
0.75
Sift
Benign
0.14
T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G
Benign
0.11
T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen
1.0
D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4
0.66
MutPred
0.42
Gain of MoRF binding (P = 0.043);.;.;.;.;.;.;.;.;.;.;.;.;.;.;
MVP
0.91
ClinPred
0.96
D
GERP RS
4.2
Varity_R
0.60
gMVP
0.73
Mutation Taster
=26/74
disease causing

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: rs878854117; hg19: chr16-2138268; API