rs1349341137

Variant summary

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

The NM_000548.5(TSC2):​c.3899T>A​(p.Met1300Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000126 in 1,590,852 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. M1300T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 7.0e-7 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

6
13

Clinical Significance

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

Conservation

PhyloP100: 1.48

Publications

2 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=0.11384317).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC2NM_000548.5 linkc.3899T>A p.Met1300Lys 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.3899T>A p.Met1300Lys missense_variant Exon 33 of 42 5 NM_000548.5 ENSP00000219476.3 P49815-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152088
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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
GnomAD4 exome
AF:
6.95e-7
AC:
1
AN:
1438764
Hom.:
0
Cov.:
32
AF XY:
0.00000140
AC XY:
1
AN XY:
713258
show subpopulations
African (AFR)
AF:
0.0000300
AC:
1
AN:
33326
American (AMR)
AF:
0.00
AC:
0
AN:
40382
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25552
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38992
South Asian (SAS)
AF:
0.00
AC:
0
AN:
82634
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50558
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5744
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1101904
Other (OTH)
AF:
0.00
AC:
0
AN:
59672
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:
0.00000658
AC:
1
AN:
152088
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74300
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000241
AC:
1
AN:
41430
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
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:
0.00
AC:
0
AN:
67972
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
⚠️ 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: 0.275
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

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
Oct 06, 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 methionine with lysine at codon 1300 of the TSC2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, 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
Oct 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with lysine, which is basic and polar, at codon 1300 of the TSC2 protein (p.Met1300Lys). 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: 951522). 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. -

Hereditary cancer-predisposing syndrome Uncertain:1
Jun 16, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.M1300K variant (also known as c.3899T>A), located in coding exon 32 of the TSC2 gene, results from a T to A substitution at nucleotide position 3899. The methionine at codon 1300 is replaced by lysine, 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
0.12
BayesDel_addAF
Uncertain
0.13
D
BayesDel_noAF
Uncertain
-0.050
CADD
Benign
17
DANN
Benign
0.83
DEOGEN2
Benign
0.39
T;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen
Benign
-0.74
Eigen_PC
Benign
-0.63
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Uncertain
0.96
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Uncertain
0.18
D
MetaRNN
Benign
0.11
T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.71
T
MutationAssessor
Benign
0.0
N;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100
1.5
PrimateAI
Benign
0.33
T
PROVEAN
Benign
-0.83
N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL
Uncertain
0.49
Sift
Benign
0.22
T;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G
Benign
0.50
T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen
0.010
B;.;.;.;B;B;.;.;B;B;.;.;.;.;.
Vest4
0.23
MutPred
0.33
Gain of ubiquitination at M1300 (P = 0.0066);.;.;.;.;.;.;Gain of ubiquitination at M1300 (P = 0.0066);.;.;.;.;.;.;.;
MVP
0.95
ClinPred
0.082
T
GERP RS
3.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.29
gMVP
0.32
Mutation Taster
=91/9
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: rs1349341137; hg19: chr16-2133711; API