16-2084966-G-T

Variant names:

• chr16-2084966-G-T
• rs45517349
• NM_000548.5:c.4509G>T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Moderate PP5_Moderate

The NM_000548.5(TSC2):​c.4509G>T​(p.Gln1503His) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q1503P) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1 O:1
• Conservation: PhyloP100: 6.62
• Publications: 5 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: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 42 uncertain in NM_000548.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-2084965-A-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 12401.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.917
• PP5: Variant 16-2084966-G-T is Pathogenic according to our data. Variant chr16-2084966-G-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 49498.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5	c.4509G>T	p.Gln1503His	missense_variant	Exon 35 of 42	ENST00000219476.9	NP_000539.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9	c.4509G>T	p.Gln1503His	missense_variant	Exon 35 of 42	5	NM_000548.5	ENSP00000219476.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Tuberous sclerosis 2 Pathogenic:1

May 22, 2022

3billion

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The variant is not observed in the gnomAD v2.1.1 dataset. Missense varaint: Protein truncation variants are a common disease-causing mechanism. In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.89; 3Cnet: 0.05). Same nucleotide change resulting in same amino acid change has been previously reported to be associated with TSC2 related disorder (PMID: 17304050). A different missense change at the same codon (p.Gln1503Pro) has been reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000012401). Therefore, this variant is classified as likely pathogenic according to the recommendation of ACMG/AMP guideline. -

Tuberous sclerosis syndrome Other:1

-

Tuberous sclerosis database (TSC2)

Significance: not provided

Review Status: no classification provided

Collection Method: curation

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.44
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Uncertain	0.48
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.92	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.87	D
MetaRNN	Pathogenic	0.92	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.93	D
MutationAssessor	Uncertain	2.3	M;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100		6.6
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-3.8	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
REVEL	Pathogenic	0.89
Sift	Benign	0.13	T;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G	Uncertain	0.0020	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Polyphen		1.0	D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4		0.91
MutPred		0.65		Loss of sheet (P = 0.0817);.;.;.;.;.;.;Loss of sheet (P = 0.0817);.;.;.;.;.;.;.;
MVP		1.0
ClinPred		0.99	D
GERP RS		4.0
Varity_R		0.63
gMVP		0.92
Mutation Taster		=1/99	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs45517349; hg19: chr16-2134967;