9-132923353-T-G

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_000368.5(TSC1):c.503A>C(p.Lys168Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,614,084 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

TSC1
NM_000368.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:8B:1

Conservation

PhyloP100: 7.46

Variant links:

Genes affected

TSC1 (HGNC:12362): (TSC complex subunit 1) This gene is a tumor suppressor gene that encodes the growth inhibitory protein hamartin. The encoded protein interacts with and stabilizes the GTPase activating protein tuberin. This hamartin-tuberin complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. This protein also functions as a co-chaperone for Hsp90 that inhibits its ATPase activity. This protein functions as a facilitator of Hsp90-mediated folding of kinase and non-kinase clients, including TSC2 and thereby preventing their ubiquitination and proteasomal degradation. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]

TSC1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2

High AC in GnomAd4 at 8 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC1	NM_000368.5 link	c.503A>C	p.Lys168Thr	missense_variant	Exon 6 of 23	ENST00000298552.9	NP_000359.1	Q92574-1Q86WV8X5D9D2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC1	ENST00000298552.9 link	c.503A>C	p.Lys168Thr	missense_variant	Exon 6 of 23	1	NM_000368.5	ENSP00000298552.3		Q92574-1
TSC1	ENST00000490179.4 link	c.503A>C	p.Lys168Thr	missense_variant	Exon 7 of 24	3		ENSP00000495533.2		A0A2R8Y6S8

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152150

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000262

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1461814

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727216

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

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:

0.0000662

GnomAD4 genome

AF:

0.0000525

AC:

AN:

152270

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74470

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.000458

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:8Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Oct 20, 2023

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The TSC1 c.503A>C (p.Lys168Thr) variant has been reported in an affected individual with young onset head and neck cancer (PMID: 34598035 (2021)). This variant has also been observed in a reportedly healthy individual (PMID: 29641532 (2018)). The frequency of this variant in the general population, 0.00026 (4/15278 chromosomes in Latino/Admixed American subpopulation (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is higher than would generally be expected for pathogenic variants in this gene. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is benign. Based on the available information, we are unable to determine the clinical significance of this variant. -

May 07, 2023

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); Reported as a germline variant of uncertain significance in a patient with young head and neck cancer (Cury et al., 2021); This variant is associated with the following publications: (PMID: 34598035) -

Hereditary cancer-predisposing syndrome

Uncertain:2

Jul 10, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.K168T variant (also known as c.503A>C), located in coding exon 4 of the TSC1 gene, results from an A to C substitution at nucleotide position 503. The lysine at codon 168 is replaced by threonine, an amino acid with similar properties. This amino acid position is highly conserved through mammals but not in all 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. -

Jul 01, 2021

Sema4, Sema4

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: curation

- -

Tuberous sclerosis 1

Uncertain:1Benign:1

Feb 03, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely 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

- -

Tuberous sclerosis syndrome

Uncertain:1

Mar 24, 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 lysine with threonine at codon 168 of the TSC1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with TSC1-related disorders in the literature. This variant has not been identified 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. -

Lymphangiomyomatosis;C1846385:Isolated focal cortical dysplasia type II;C1854465:Tuberous sclerosis 1

Uncertain:1

Jan 16, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Isolated focal cortical dysplasia type II

Uncertain:1

Oct 08, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.21

BayesDel_addAF

Pathogenic

0.19

BayesDel_noAF

Uncertain

0.030

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.44

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

Eigen

Uncertain

0.33

Eigen_PC

Uncertain

0.42

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.97

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

M_CAP

Uncertain

0.15

MetaRNN

Uncertain

0.45

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

MetaSVM

Uncertain

0.36

MutationAssessor

Benign

1.9

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

PrimateAI

Uncertain

0.53

PROVEAN

Benign

-0.77

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

REVEL

Uncertain

0.51

Sift

Benign

0.18

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

Sift4G

Uncertain

0.024

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

Polyphen

0.028

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

Vest4

0.41

MVP

0.36

MPC

1.3

ClinPred

0.75

GERP RS

5.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.16

gMVP

0.31

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.080

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