NM_000548.5:c.3304G>A

Variant names:

• chr16-2079576-G-A
• rs775584262
• NM_000548.5:c.3304G>A

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP6

The NM_000548.5(TSC2):​c.3304G>A​(p.Val1102Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,459,164 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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. V1102G) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6 B:2
• Conservation: PhyloP100: 1.96
• Publications: 2 publications found

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 Gene-Disease associations (from GenCC):

• tuberous sclerosis

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• tuberous sclerosis 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, Ambry Genetics
• lymphangioleiomyomatosis

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• tuberous sclerosis complex

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.1506786).
• BP6: Variant 16-2079576-G-A is Benign according to our data. Variant chr16-2079576-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 535906.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5	c.3304G>A	p.Val1102Met	missense_variant	Exon 29 of 42	ENST00000219476.9	NP_000539.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9	c.3304G>A	p.Val1102Met	missense_variant	Exon 29 of 42	5	NM_000548.5	ENSP00000219476.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000409 AC: 1 AN: 244498 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000909

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000206 AC: 3 AN: 1459164 Hom.: 0 Cov.: 31 AF XY: 0.00000276 AC XY: 2 AN XY: 725780

African (AFR) AF: 0.00 AC: 0 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44528

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26078

East Asian (EAS) AF: 0.00 AC: 0 AN: 39626

South Asian (SAS) AF: 0.00 AC: 0 AN: 86024

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51968

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111450

Other (OTH) AF: 0.00 AC: 0 AN: 60254

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000829 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:6 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Tuberous sclerosis syndrome Uncertain:2

Mar 08, 2024

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 31, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces valine with methionine at codon 1102 of the TSC2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with TSC2-related disorders in the literature. This variant has been identified in 1/244498 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. -

Tuberous sclerosis 2 Uncertain:1 Benign:1

Nov 07, 2021

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 16, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Lymphangiomyomatosis;C1846385:Isolated focal cortical dysplasia type II;C1860707:Tuberous sclerosis 2 Uncertain:1

May 17, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Dec 30, 2019

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Isolated focal cortical dysplasia type II Uncertain:1

May 26, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Benign:1

Apr 27, 2023

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.089
BayesDel_addAF	Uncertain	0.091	D
BayesDel_noAF	Benign	-0.11
CADD	Benign	15
DANN	Uncertain	0.98
DEOGEN2	Benign	0.41	T;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Benign	-0.75
Eigen_PC	Benign	-0.81
FATHMM_MKL	Benign	0.50	D
LIST_S2	Uncertain	0.87	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.12	D
MetaRNN	Benign	0.15	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.47	T
MutationAssessor	Benign	1.1	L;.;.;.;.;.;.;.;.;L;.;.;.;.;.
PhyloP100		2.0
PrimateAI	Uncertain	0.51	T
PROVEAN	Benign	-0.77	N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL	Uncertain	0.48
Sift	Uncertain	0.011	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G	Benign	0.15	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen		0.62	P;.;.;.;B;P;.;.;B;B;.;.;.;.;.
Vest4		0.40
MutPred		0.14		Loss of sheet (P = 0.0228);.;Loss of sheet (P = 0.0228);.;.;.;.;Loss of sheet (P = 0.0228);.;Loss of sheet (P = 0.0228);.;.;.;.;.;
MVP		0.84
ClinPred		0.073	T
GERP RS		-0.88
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.061
gMVP		0.45
Mutation Taster		=97/3	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs775584262; hg19: chr16-2129577;