rs758677443

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000548.5(TSC2):​c.3893T>C​(p.Val1298Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000315 in 1,587,444 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. V1298M) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 34)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

5
14

Clinical Significance

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

Conservation

PhyloP100: 0.863

Publications

1 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 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.09303856).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC2NM_000548.5 linkc.3893T>C p.Val1298Ala missense_variant Exon 33 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.3893T>C p.Val1298Ala missense_variant Exon 33 of 42 5 NM_000548.5 ENSP00000219476.3 P49815-1

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
151994
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000965
AC:
2
AN:
207274
AF XY:
0.0000180
show subpopulations
Gnomad AFR exome
AF:
0.000158
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000209
AC:
3
AN:
1435450
Hom.:
0
Cov.:
32
AF XY:
0.00000281
AC XY:
2
AN XY:
711296
show subpopulations
African (AFR)
AF:
0.0000901
AC:
3
AN:
33282
American (AMR)
AF:
0.00
AC:
0
AN:
39878
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25500
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38886
South Asian (SAS)
AF:
0.00
AC:
0
AN:
82340
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50330
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5730
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1100006
Other (OTH)
AF:
0.00
AC:
0
AN:
59498
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
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:
0.0000132
AC:
2
AN:
151994
Hom.:
0
Cov.:
34
AF XY:
0.0000269
AC XY:
2
AN XY:
74240
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41382
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67960
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
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

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:
0.0000151
ExAC
AF:
0.0000167
AC:
2

ClinVar

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

Submissions by phenotype

Tuberous sclerosis syndrome Uncertain:1
Dec 18, 2023
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces valine with alanine at codon 1298 of the TSC2 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with tuberous sclerosis complex in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Tuberous sclerosis 2 Uncertain:1
May 03, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 1298 of the TSC2 protein (p.Val1298Ala). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. 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: 577294). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt TSC2 protein function. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1
Feb 28, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.V1298A variant (also known as c.3893T>C), located in coding exon 32 of the TSC2 gene, results from a T to C substitution at nucleotide position 3893. The valine at codon 1298 is replaced by alanine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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
Benign
0.10
BayesDel_addAF
Uncertain
0.14
D
BayesDel_noAF
Uncertain
-0.040
CADD
Benign
13
DANN
Benign
0.52
DEOGEN2
Benign
0.36
T;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen
Benign
-1.0
Eigen_PC
Benign
-0.97
FATHMM_MKL
Uncertain
0.82
D
LIST_S2
Benign
0.72
T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
M_CAP
Uncertain
0.18
D
MetaRNN
Benign
0.093
T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.64
T
MutationAssessor
Benign
1.8
L;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100
0.86
PrimateAI
Benign
0.36
T
PROVEAN
Benign
-0.65
N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL
Uncertain
0.58
Sift
Benign
0.16
T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G
Benign
0.54
T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen
0.089
B;.;.;.;B;B;.;.;B;B;.;.;.;.;.
Vest4
0.18
MutPred
0.23
Loss of sheet (P = 0.003);.;.;.;.;.;.;Loss of sheet (P = 0.003);.;.;.;.;.;.;.;
MVP
0.99
ClinPred
0.021
T
GERP RS
0.35
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.0
Varity_R
0.040
gMVP
0.30
Mutation Taster
=95/5
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
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: rs758677443; hg19: chr16-2133705; API