16-2057150-T-G

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2PM5PP3

The NM_000548.5(TSC2):c.820T>G(p.Tyr274Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000129 in 1,551,654 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y274N) has been classified as Likely pathogenic.

Frequency

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

Exomes 𝑓: 7.1e-7 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 3.23

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr16-2057150-T-A is described in Lovd as [Likely_pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.804

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5 link	c.820T>G	p.Tyr274Asp	missense_variant	Exon 9 of 42	ENST00000219476.9	NP_000539.2	P49815-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9 link	c.820T>G	p.Tyr274Asp	missense_variant	Exon 9 of 42	5	NM_000548.5	ENSP00000219476.3		P49815-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152178

Hom.:

Cov.:

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:

7.15e-7

AC:

AN:

1399476

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

690254

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

9.27e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152178

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74338

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

Bravo

AF:

0.0000113

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000123

AC:

ExAC

AF:

0.0000120

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Tuberous sclerosis 2

Uncertain:1

Feb 11, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with aspartic acid, which is acidic and polar, at codon 274 of the TSC2 protein (p.Tyr274Asp). 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: 405958). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae 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 20, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Y274D variant (also known as c.820T>G), located in coding exon 8 of the TSC2 gene, results from a T to G substitution at nucleotide position 820. The tyrosine at codon 274 is replaced by aspartic acid, an amino acid with highly dissimilar properties. This amino acid position is conserved. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.57

BayesDel_addAF

Pathogenic

0.38

BayesDel_noAF

Pathogenic

0.30

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Pathogenic

0.86

D;.;.;.;.;.;.;.;.;.;.;.;T;.;T

Eigen

Uncertain

0.24

Eigen_PC

Uncertain

0.23

FATHMM_MKL

Uncertain

0.90

LIST_S2

Benign

0.80

T;T;T;T;T;T;T;T;T;T;T;T;T;T;T

M_CAP

Pathogenic

0.39

MetaRNN

Pathogenic

0.80

D;D;D;D;D;D;D;D;D;D;D;D;D;D;D

MetaSVM

Uncertain

-0.22

MutationAssessor

Uncertain

2.3

M;.;.;.;M;M;.;.;.;M;.;M;.;.;.

PrimateAI

Uncertain

0.62

PROVEAN

Pathogenic

-6.4

D;.;.;D;.;D;.;.;D;D;.;.;.;.;D

REVEL

Uncertain

0.44

Sift

Uncertain

0.0010

D;.;.;D;.;D;.;.;D;D;.;.;.;.;D

Sift4G

Pathogenic

0.0

D;.;.;D;.;D;.;.;D;D;.;.;.;.;D

Polyphen

1.0

D;.;.;.;P;P;.;.;B;B;.;.;.;.;.

Vest4

0.82

MVP

0.96

ClinPred

0.96

GERP RS

4.7

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.88

gMVP

0.71

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

LitVar

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over