Genetic Variant TSC2:p.Ala1349Ser (chr16-2084267-G-T) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_000548.5(TSC2):c.4045G>T(p.Ala1349Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,456,522 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign 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. A1349T) has been classified as Benign.

Frequency

Genomes: not found (cov: 34)

Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.0100

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:

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ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.050927788).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5 link	c.4045G>T	p.Ala1349Ser	missense_variant	Exon 34 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.4045G>T	p.Ala1349Ser	missense_variant	Exon 34 of 42	5	NM_000548.5	ENSP00000219476.3		P49815-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

6.87e-7

AC:

AN:

1456522

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

724144

show subpopulations

Gnomad4 AFR exome

AF:

0.0000300

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:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Tuberous sclerosis 2

Uncertain:1

Feb 22, 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 1349 of the TSC2 protein (p.Ala1349Ser). 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. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.074

BayesDel_addAF

Uncertain

0.055

BayesDel_noAF

Benign

-0.16

CADD

Benign

0.022

DANN

Benign

0.45

DEOGEN2

Benign

0.33

T;.;.;.;.;.;.;.;.;.;.;.;T;.;T

Eigen

Benign

-1.4

Eigen_PC

Benign

-1.4

FATHMM_MKL

Benign

0.061

LIST_S2

Benign

0.83

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

M_CAP

Benign

0.065

MetaRNN

Benign

0.051

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

MetaSVM

Benign

-0.76

MutationAssessor

Benign

0.14

N;.;.;.;.;.;.;.;.;.;.;.;.;.;.

PrimateAI

Benign

0.26

PROVEAN

Benign

-0.52

N;.;.;N;.;N;.;.;N;N;.;.;.;.;N

REVEL

Uncertain

0.58

Sift

Benign

0.61

T;.;.;T;.;T;.;.;T;T;.;.;.;.;T

Sift4G

Benign

0.86

T;.;.;T;.;T;.;.;T;T;.;.;.;.;T

Polyphen

0.0010

B;.;.;.;B;B;.;.;B;B;.;.;.;.;.

Vest4

0.14

MutPred

0.19

Gain of loop (P = 0.0111);.;.;.;.;.;.;Gain of loop (P = 0.0111);.;.;.;.;.;.;.;

MVP

0.99

ClinPred

0.045

GERP RS

-1.7

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.051

gMVP

0.31

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

No publications associated with this variant yet.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over