16-2079657-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP3BS2

The NM_000548.5(TSC2):​c.3385C>T​(p.Arg1129Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000502 in 1,594,812 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000049 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

8
10
1

Clinical Significance

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

Conservation

PhyloP100: 2.81
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.823
BS2
High AC in GnomAdExome4 at 7 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC2NM_000548.5 linkc.3385C>T p.Arg1129Cys missense_variant Exon 29 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.3385C>T p.Arg1129Cys missense_variant Exon 29 of 42 5 NM_000548.5 ENSP00000219476.3 P49815-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152194
Hom.:
0
Cov.:
33
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
GnomAD3 exomes
AF:
0.0000188
AC:
4
AN:
212436
Hom.:
0
AF XY:
0.00000869
AC XY:
1
AN XY:
115132
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000324
Gnomad ASJ exome
AF:
0.000108
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000566
Gnomad NFE exome
AF:
0.0000107
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000485
AC:
7
AN:
1442618
Hom.:
0
Cov.:
31
AF XY:
0.00000419
AC XY:
3
AN XY:
716042
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000237
Gnomad4 ASJ exome
AF:
0.0000388
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.0000198
Gnomad4 NFE exome
AF:
0.00000362
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152194
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74360
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000868
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Nov 11, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: TSC2 c.3385C>T (p.Arg1129Cys) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.9e-05 in 212436 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.3385C>T has been reported in the literature in at least one individual affected with Tuberous Sclerosis Complex (e.g., Meng_2021). This report does not provide unequivocal conclusions about association of the variant with Tuberous Sclerosis Complex. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 32917966). ClinVar contains an entry for this variant (Variation ID: 406032). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Tuberous sclerosis syndrome Uncertain:1
Jun 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 arginine with cysteine at codon 1129 of the TSC2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with clinically suspected tuberous sclerosis complex (PMID: 32917966). This variant has been identified in 4/212436 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
Jan 19, 2023
PreventionGenetics, part of Exact Sciences
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The TSC2 c.3385C>T variant is predicted to result in the amino acid substitution p.Arg1129Cys. This variant has been reported in and individual with cortical dysplasia and tuberous sclerosis complex-associated neuropsychiatric disorder (Table S1, ID: NP15D2345, Meng et al. 2021. PubMed ID: 32917966). It has also been reported in an individual with a pancreatic neuroendocrine tumor (Midie et al. 2022. PubMed ID: 36140756). This variant is reported in 4 of ~212,000 alleles in gnomAD (http://gnomad.broadinstitute.org/variant/16-2129658-C-T) and has conflicting interpretations of likely benign and uncertain significance in ClinVar (https://preview.ncbi.nlm.nih.gov/clinvar/variation/406032/). 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 Uncertain:1
Mar 28, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.R1129C variant (also known as c.3385C>T), located in coding exon 28 of the TSC2 gene, results from a C to T substitution at nucleotide position 3385. The arginine at codon 1129 is replaced by cysteine, an amino acid with highly dissimilar properties. This variant was detected in 1/347 Chinese patients with clinically suspected tuberous sclerosis complex (TSC) and called a variant of uncertain significance by the authors (Meng Y et al. J Hum Genet, 2021 Mar;66:227-236). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Tuberous sclerosis 2 Benign:1
Jan 21, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.50
BayesDel_addAF
Pathogenic
0.35
D
BayesDel_noAF
Pathogenic
0.36
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.79
D;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen
Uncertain
0.56
Eigen_PC
Uncertain
0.50
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.96
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.66
D
MetaRNN
Pathogenic
0.82
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.76
D
MutationAssessor
Uncertain
2.3
M;.;.;.;.;.;.;.;.;M;.;.;.;.;.
PrimateAI
Pathogenic
0.79
T
PROVEAN
Uncertain
-3.9
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
REVEL
Pathogenic
0.81
Sift
Uncertain
0.0010
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G
Pathogenic
0.0010
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Polyphen
1.0
D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4
0.86
MutPred
0.38
Gain of sheet (P = 0.0149);.;Gain of sheet (P = 0.0149);.;.;.;.;Gain of sheet (P = 0.0149);.;Gain of sheet (P = 0.0149);.;.;.;.;.;
MVP
0.98
ClinPred
0.94
D
GERP RS
4.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.8
Varity_R
0.39
gMVP
0.51

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.12
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs1028039505; hg19: chr16-2129658; COSMIC: COSV54771064; COSMIC: COSV54771064; API