rs45448791

Positions:

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_StrongBS2

The NM_000548.5(TSC2):c.4313G>A(p.Arg1438Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000994 in 1,609,372 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. 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. R1438W) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 34)

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: -0.917

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 Benign. Variant got -8 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.067894936).

BS2

High AC in GnomAdExome4 at 15 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TSC2	NM_000548.5 linkuse as main transcript	c.4313G>A	p.Arg1438Gln	missense_variant	34/42	ENST00000219476.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC2	ENST00000219476.9 linkuse as main transcript	c.4313G>A	p.Arg1438Gln	missense_variant	34/42	5	NM_000548.5		P49815-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152248

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:

0.0000941

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000168

AC:

AN:

238686

Hom.:

AF XY:

0.00

AC XY:

AN XY:

130884

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000562

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000279

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000103

AC:

AN:

1457006

Hom.:

Cov.:

AF XY:

0.00000966

AC XY:

AN XY:

724854

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.0000199

Gnomad4 NFE exome

AF:

0.00000990

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000656

AC:

AN:

152366

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74510

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:

0.0000941

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ExAC

AF:

0.00000830

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4Benign:1Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Tuberous sclerosis 2

Uncertain:1Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 20, 2023	- -

Tuberous sclerosis syndrome

Uncertain:1Other:1

not provided, no classification provided	curation	Tuberous sclerosis database (TSC2)	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Nov 30, 2023	- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jul 19, 2024

Variant summary: TSC2 c.4313G>A (p.Arg1438Gln) results in a conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 9.9e-06 in 1609372 control chromosomes, predominantly at a frequency of 2.2e-05 within the East Asian subpopulation in the gnomAD database v4. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.4313G>A has been reported in the literature in four individuals affected with Tuberous Sclerosis Complex, including one occurrence of arising de novo (Roberts_2004, Sudarshan_2020). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 15121797, 34849272). ClinVar contains an entry for this variant (Variation ID: 50124). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 19, 2019

The p.R1438Q variant (also known as c.4313G>A), located in coding exon 33 of the TSC2 gene, results from a G to A substitution at nucleotide position 4313. The arginine at codon 1438 is replaced by glutamine, an amino acid with highly similar properties. This variant was reportedly de novo in an individual with tuberous sclerosis (Roberts PS et al. J. Med. Genet., 2004 May;41:e69). This amino acid position is poorly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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

Benign

0.063

BayesDel_addAF

Uncertain

0.12

BayesDel_noAF

Uncertain

0.0

CADD

Benign

3.8

DANN

Uncertain

0.98

DEOGEN2

Benign

0.37

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

Eigen

Benign

-1.2

Eigen_PC

Benign

-1.3

FATHMM_MKL

Benign

0.10

LIST_S2

Uncertain

0.88

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

M_CAP

Benign

0.072

MetaRNN

Benign

0.068

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

MetaSVM

Benign

-0.72

MutationAssessor

Benign

0.60

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

MutationTaster

Benign

1.0

N;N;N;N;N;N;N

PrimateAI

Benign

0.38

PROVEAN

Benign

-0.48

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

REVEL

Uncertain

0.60

Sift

Benign

0.13

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

Sift4G

Benign

0.27

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

Polyphen

0.0040

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

Vest4

0.17

MutPred

0.44

Loss of glycosylation at S1437 (P = 0.1082);.;.;.;.;.;.;Loss of glycosylation at S1437 (P = 0.1082);.;.;.;.;.;.;.;

MVP

1.0

ClinPred

0.031

GERP RS

-6.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.2

Varity_R

0.030

gMVP

0.24

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.040

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