16-2085299-G-A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM1BP6BS2

The NM_000548.5(TSC2):​c.4639G>A​(p.Val1547Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000211 in 1,612,608 control chromosomes in the GnomAD database, including 1 homozygotes. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V1547G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000022 ( 1 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

4
10
4

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:4B:4

Conservation

PhyloP100: 6.67

Publications

9 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: Likely_benign. The variant received -3 ACMG points.

PM1
In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 36 uncertain in NM_000548.5
BP6
Variant 16-2085299-G-A is Benign according to our data. Variant chr16-2085299-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 238056.
BS2
High AC in GnomAdExome4 at 32 AD gene.

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.4639G>Ap.Val1547Ile
missense
Exon 36 of 42NP_000539.2
TSC2
NM_001406663.1
c.4636G>Ap.Val1546Ile
missense
Exon 36 of 42NP_001393592.1
TSC2
NM_001114382.3
c.4570G>Ap.Val1524Ile
missense
Exon 35 of 41NP_001107854.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
TSC2
ENST00000219476.9
TSL:5 MANE Select
c.4639G>Ap.Val1547Ile
missense
Exon 36 of 42ENSP00000219476.3
TSC2
ENST00000350773.9
TSL:1
c.4570G>Ap.Val1524Ile
missense
Exon 35 of 41ENSP00000344383.4
TSC2
ENST00000401874.7
TSL:1
c.4438G>Ap.Val1480Ile
missense
Exon 34 of 40ENSP00000384468.2

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152214
Hom.:
0
Cov.:
34
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000280
AC:
7
AN:
249908
AF XY:
0.0000369
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000889
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000219
AC:
32
AN:
1460394
Hom.:
1
Cov.:
33
AF XY:
0.0000303
AC XY:
22
AN XY:
726500
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39698
South Asian (SAS)
AF:
0.000162
AC:
14
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52068
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1111910
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60370
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.490
Heterozygous variant carriers
0
2
4
7
9
11
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:
0.0000131
AC:
2
AN:
152214
Hom.:
0
Cov.:
34
AF XY:
0.0000134
AC XY:
1
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41462
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:
5194
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
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:
0.0000302
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:4Benign:4
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Tuberous sclerosis 2 Benign:3
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Nov 07, 2021
Genome-Nilou Lab
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Aug 23, 2024
Myriad Genetics, Inc.
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign. This variant has been observed at a population frequency that is significantly greater than expected given the associated disease prevalence and penetrance.

not provided Uncertain:2
May 03, 2024
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Dec 12, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Identified as a somatic variant in the brain of a patient with focal cortical dysplasia type IIa; this patient did not have any features of TSC (Lim et al., 2017); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously reported as a pathogenic or benign germline variant to our knowledge; This variant is associated with the following publications: (PMID: 28215400, 18466115)

Isolated focal cortical dysplasia type II Pathogenic:1
Apr 11, 2017
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

Tuberous sclerosis syndrome Uncertain:1
May 09, 2024
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 isoleucine at codon 1547 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 TSC2-related disorders in the literature. This variant has been identified in 7/249908 chromosomes 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.

TSC2-related disorder Uncertain:1
Aug 16, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The TSC2 c.4639G>A variant is predicted to result in the amino acid substitution p.Val1547Ile. This variant was identified as a somatic variant in the brain of a patient with focal cortical dysplasia type IIa (Lim et al 2017. PubMed ID: 28215400). This variant is reported in 0.016% of alleles in individuals of South Asian descent in gnomAD. This variant has interpretations ranging from benign to pathogenic in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/238056/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence.

Hereditary cancer-predisposing syndrome Benign:1
Jan 19, 2021
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Uncertain
0.064
T
BayesDel_noAF
Uncertain
0.11
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.46
T
Eigen
Uncertain
0.45
Eigen_PC
Uncertain
0.39
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.96
D
M_CAP
Pathogenic
0.50
D
MetaRNN
Uncertain
0.59
D
MetaSVM
Pathogenic
0.96
D
MutationAssessor
Benign
1.9
L
PhyloP100
6.7
PrimateAI
Uncertain
0.67
T
PROVEAN
Benign
-0.71
N
REVEL
Pathogenic
0.67
Sift
Benign
0.055
T
Sift4G
Uncertain
0.025
D
Polyphen
1.0
D
Vest4
0.55
MutPred
0.51
Loss of sheet (P = 0.0817)
MVP
0.62
ClinPred
0.33
T
GERP RS
4.5
Varity_R
0.17
gMVP
0.48
Mutation Taster
=64/36
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.11
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: rs745895675; hg19: chr16-2135300; COSMIC: COSV51911416; API