chr16-2053345-G-A

Variant summary

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

The NM_000548.5(TSC2):​c.229G>A​(p.Ala77Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000379 in 1,581,224 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. A77S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000028 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

5
13
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 9.61

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 0 ACMG points.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC2NM_000548.5 linkc.229G>A p.Ala77Thr missense_variant Exon 4 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.229G>A p.Ala77Thr missense_variant Exon 4 of 42 5 NM_000548.5 ENSP00000219476.3 P49815-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152244
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000502
AC:
1
AN:
199024
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000342
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:
0.00000280
AC:
4
AN:
1428980
Hom.:
0
Cov.:
31
AF XY:
0.00000424
AC XY:
3
AN XY:
707850
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32844
American (AMR)
AF:
0.0000250
AC:
1
AN:
39984
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25504
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38086
South Asian (SAS)
AF:
0.0000123
AC:
1
AN:
81346
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50532
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4860
European-Non Finnish (NFE)
AF:
0.00000182
AC:
2
AN:
1096734
Other (OTH)
AF:
0.00
AC:
0
AN:
59090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.438
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:
0.0000131
AC:
2
AN:
152244
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74388
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:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68048
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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000250
AC:
3

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:2Benign:1
Jan 10, 2020
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

Sep 21, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

not provided Uncertain:2
Dec 22, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on 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) -

Sep 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:1
Aug 21, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.A77T variant (also known as c.229G>A), located in coding exon 3 of the TSC2 gene, results from a G to A substitution at nucleotide position 229. The alanine at codon 77 is replaced by threonine, 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. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.65
BayesDel_addAF
Pathogenic
0.24
D
BayesDel_noAF
Uncertain
0.10
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.74
D;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen
Uncertain
0.57
Eigen_PC
Uncertain
0.56
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Uncertain
0.96
D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.50
D
MetaRNN
Uncertain
0.66
D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.045
D
MutationAssessor
Uncertain
2.1
M;.;.;.;M;M;.;.;M;.;M;.;.;.
PhyloP100
9.6
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-3.0
D;.;.;D;.;D;.;.;D;.;.;.;.;D
REVEL
Pathogenic
0.65
Sift
Uncertain
0.0030
D;.;.;D;.;D;.;.;D;.;.;.;.;D
Sift4G
Uncertain
0.0060
D;.;.;D;.;D;.;.;D;.;.;.;.;D
Polyphen
1.0
D;.;.;.;.;D;.;.;P;.;.;.;.;.
Vest4
0.83
MutPred
0.45
Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);.;Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);.;
MVP
0.76
ClinPred
0.93
D
GERP RS
4.8
PromoterAI
0.0080
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.49
gMVP
0.56
Mutation Taster
=34/66
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.060
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: rs777459404; hg19: chr16-2103346; COSMIC: COSV54755568; API