16-2070570-C-G

Variant names:

• chr16-2070570-C-G
• rs45469298
• NM_000548.5:c.1831C>G

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000548.5(TSC2):​c.1831C>G​(p.Arg611Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R611W) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2 O:1
• Conservation: PhyloP100: 2.17
• Publications: 41 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 18 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 11 benign, 33 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 chr16-2070570-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 49643.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.964
• PP5: Variant 16-2070570-C-G is Pathogenic according to our data. Variant chr16-2070570-C-G is described in ClinVar as Pathogenic. ClinVar VariationId is 49177.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5	c.1831C>G	p.Arg611Gly	missense_variant	Exon 17 of 42	ENST00000219476.9	NP_000539.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9	c.1831C>G	p.Arg611Gly	missense_variant	Exon 17 of 42	5	NM_000548.5	ENSP00000219476.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Tuberous sclerosis syndrome Pathogenic:1 Other:1

-

Tuberous sclerosis database (TSC2)

Significance: not provided

Review Status: no classification provided

Collection Method: curation

- -

Feb 18, 2025

Clinical Genetics Laboratory, Skane University Hospital Lund

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ACMG criteria used: PS2, PS4_Supporting, PM2, PM5, PP3 -

Tuberous sclerosis 2 Pathogenic:1

Mar 24, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Arg611 amino acid residue in TSC2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 9463313, 17304050, 11741832, 21309039). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. This sequence change replaces arginine with glycine at codon 611 of the TSC2 protein (p.Arg611Gly). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and glycine. This variant is not present in population databases (ExAC no frequency). This variant has been reported in individual(s) with tuberous sclerosis complex (PMID: 21520333, Invitae). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 49177). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.42
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D;.;.;.;.;.;.;.;.;.;.;.;D;.;D
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.93	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.96	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.88	D
MutationAssessor	Pathogenic	2.9	M;.;.;.;M;M;.;.;.;M;.;M;.;.;.
PhyloP100		2.2
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-6.3	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0010	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G	Uncertain	0.0070	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Polyphen		1.0	D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4		0.96
MutPred		0.81		Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);.;Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);.;Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);Loss of helix (P = 0.0237);.;
MVP		0.99
ClinPred		0.98	D
GERP RS		4.5
Varity_R		0.92
gMVP		0.92
Mutation Taster		=23/77	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs45469298; hg19: chr16-2120571;