16-2057144-G-T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1PM2

The NM_000548.5(TSC2):​c.814G>T​(p.Ala272Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000193 in 1,551,588 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. A272T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

2
10
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 7.53

Publications

13 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 4 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 42 uncertain in NM_000548.5
PM2
Very rare variant in population databases, with high coverage;

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000548.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TSC2
NM_000548.5
MANE Select
c.814G>Tp.Ala272Ser
missense
Exon 9 of 42NP_000539.2
TSC2
NM_001406663.1
c.814G>Tp.Ala272Ser
missense
Exon 9 of 42NP_001393592.1
TSC2
NM_001114382.3
c.814G>Tp.Ala272Ser
missense
Exon 9 of 41NP_001107854.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TSC2
ENST00000219476.9
TSL:5 MANE Select
c.814G>Tp.Ala272Ser
missense
Exon 9 of 42ENSP00000219476.3
TSC2
ENST00000350773.9
TSL:1
c.814G>Tp.Ala272Ser
missense
Exon 9 of 41ENSP00000344383.4
TSC2
ENST00000401874.7
TSL:1
c.814G>Tp.Ala272Ser
missense
Exon 9 of 40ENSP00000384468.2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152170
Hom.:
0
Cov.:
32
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:
0.00000143
AC:
2
AN:
1399418
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
690226
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31600
American (AMR)
AF:
0.00
AC:
0
AN:
35724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25182
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35742
South Asian (SAS)
AF:
0.00
AC:
0
AN:
79268
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49196
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5660
European-Non Finnish (NFE)
AF:
0.00000185
AC:
2
AN:
1079032
Other (OTH)
AF:
0.00
AC:
0
AN:
58014
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
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:
152170
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74326
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41432
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:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
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:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Tuberous sclerosis syndrome Uncertain:1
Jan 11, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Tuberous sclerosis 2 Uncertain:1
Sep 06, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 272 of the TSC2 protein (p.Ala272Ser). 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: 576842). 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
Sep 28, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); 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; This variant is associated with the following publications: (PMID: 18466115)

Hereditary cancer-predisposing syndrome Uncertain:1
Jun 14, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.A272S variant (also known as c.814G>T), located in coding exon 8 of the TSC2 gene, results from a G to T substitution at nucleotide position 814. The alanine at codon 272 is replaced by serine, an amino acid with similar properties. This amino acid position is highly 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 v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.23
BayesDel_addAF
Pathogenic
0.20
D
BayesDel_noAF
Uncertain
0.050
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Benign
0.38
T
Eigen
Uncertain
0.45
Eigen_PC
Uncertain
0.44
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Benign
0.85
D
M_CAP
Pathogenic
0.30
D
MetaRNN
Uncertain
0.71
D
MetaSVM
Uncertain
0.22
D
MutationAssessor
Benign
1.5
L
PhyloP100
7.5
PrimateAI
Uncertain
0.76
T
PROVEAN
Benign
-0.75
N
REVEL
Uncertain
0.59
Sift
Benign
0.15
T
Sift4G
Uncertain
0.049
D
Polyphen
1.0
D
Vest4
0.64
MutPred
0.53
Gain of loop (P = 0.0435)
MVP
0.74
ClinPred
0.88
D
GERP RS
4.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.35
gMVP
0.40
Mutation Taster
=71/29
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: rs373818076; hg19: chr16-2107145; API