16-2085244-G-T

Variant names:

• chr16-2085244-G-T
• rs199848388
• NM_000548.5:c.4584G>T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000548.5(TSC2):​c.4584G>T​(p.Glu1528Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,410 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E1528Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: -0.109
• Publications: 3 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: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000548.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC2	NM_000548.5	MANE Select	c.4584G>T	p.Glu1528Asp	missense	Exon 36 of 42	NP_000539.2
	TSC2	NM_001406663.1		c.4581G>T	p.Glu1527Asp	missense	Exon 36 of 42	NP_001393592.1
	TSC2	NM_001114382.3		c.4515G>T	p.Glu1505Asp	missense	Exon 35 of 41	NP_001107854.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC2	ENST00000219476.9	TSL:5 MANE Select	c.4584G>T	p.Glu1528Asp	missense	Exon 36 of 42	ENSP00000219476.3
	TSC2	ENST00000350773.9	TSL:1	c.4515G>T	p.Glu1505Asp	missense	Exon 35 of 41	ENSP00000344383.4
	TSC2	ENST00000401874.7	TSL:1	c.4383G>T	p.Glu1461Asp	missense	Exon 34 of 40	ENSP00000384468.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460410 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 726506

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52074

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111918

Other (OTH) AF: 0.00 AC: 0 AN: 60372

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:2

Nov 07, 2021

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Apr 22, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamic acid, which is acidic and polar, with aspartic acid, which is acidic and polar, at codon 1528 of the TSC2 protein (p.Glu1528Asp). 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. ClinVar contains an entry for this variant (Variation ID: 41743). 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%. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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.

not provided Uncertain:1

Jul 13, 2012

Biesecker Lab/Clinical Genomics Section, National Institutes of Health

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: research

Isolated focal cortical dysplasia type II Uncertain:1

Jul 11, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Hereditary cancer-predisposing syndrome Uncertain:1

Mar 07, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.E1528D variant (also known as c.4584G>T), located in coding exon 35 of the TSC2 gene, results from a G to T substitution at nucleotide position 4584. The glutamic acid at codon 1528 is replaced by aspartic acid, an amino acid with highly similar properties. This variant was detected as a secondary finding in 1 out of 572 ClinSeq participants, unselected for personal or family history of cancer, who underwent exome sequencing; however, the clinical information for this particular individual was not provided (Johnston JJ et al. Am. J. Hum. Genet., 2012 Jul;91:97-108). This amino acid position is well conserved in available vertebrate species. In addition, as a missense variant, this alteration is predicted to be tolerated by in silico analysis. In silico splice site analysis predicts that this alteration will result in the creation or strengthening of a novel splice acceptor site; however, direct evidence is insufficient at this time (Ambry internal data). Based on the available evidence, the clinical significance of this variant remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.030
CADD	Uncertain	26
DANN	Uncertain	0.99
DEOGEN2	Benign	0.39	T
Eigen	Benign	-0.62
Eigen_PC	Benign	-0.54
FATHMM_MKL	Benign	0.53	D
LIST_S2	Uncertain	0.89	D
M_CAP	Uncertain	0.13	D
MetaRNN	Benign	0.20	T
MetaSVM	Uncertain	-0.070	T
MutationAssessor	Benign	0.23	N
PhyloP100		-0.11
PrimateAI	Uncertain	0.68	T
PROVEAN	Benign	-0.48	N
REVEL	Uncertain	0.57
Sift	Benign	0.37	T
Sift4G	Benign	0.63	T
Polyphen		0.26	B
Vest4		0.46
MutPred		0.37		Loss of helix (P = 0.0196)
MVP		0.94
ClinPred		0.45	T
GERP RS		-0.060
Varity_R		0.077
gMVP		0.36
Mutation Taster		=92/8	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.75		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.75		Position offset: 13

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

Other links and lift over

dbSNP: rs199848388; hg19: chr16-2135245;