16-2079637-G-T

Variant names:

• chr16-2079637-G-T
• rs369536711
• NM_000548.5:c.3365G>T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000548.5(TSC2):​c.3365G>T​(p.Arg1122Leu) 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 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. R1122H) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.55
• Publications: 0 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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.32745174).

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.3365G>T	p.Arg1122Leu	missense	Exon 29 of 42	NP_000539.2
	TSC2	NM_001406663.1		c.3362G>T	p.Arg1121Leu	missense	Exon 29 of 42	NP_001393592.1
	TSC2	NM_001114382.3		c.3365G>T	p.Arg1122Leu	missense	Exon 29 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.3365G>T	p.Arg1122Leu	missense	Exon 29 of 42	ENSP00000219476.3
	TSC2	ENST00000350773.9	TSL:1	c.3365G>T	p.Arg1122Leu	missense	Exon 29 of 41	ENSP00000344383.4
	TSC2	ENST00000401874.7	TSL:1	c.3233G>T	p.Arg1078Leu	missense	Exon 28 of 40	ENSP00000384468.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1454848 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 723222

African (AFR) AF: 0.00 AC: 0 AN: 33412

American (AMR) AF: 0.00 AC: 0 AN: 43974

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25990

East Asian (EAS) AF: 0.00 AC: 0 AN: 39474

South Asian (SAS) AF: 0.00 AC: 0 AN: 85368

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51520

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5434

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1109682

Other (OTH) AF: 0.00 AC: 0 AN: 59994

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:1

Jan 14, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 1122 of the TSC2 protein (p.Arg1122Leu). 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: 1429885). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt TSC2 protein function with a negative predictive value of 95%. 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.

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

Oct 23, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Hereditary cancer-predisposing syndrome Uncertain:1

Jul 12, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R1122L variant (also known as c.3365G>T), located in coding exon 28 of the TSC2 gene, results from a G to T substitution at nucleotide position 3365. The arginine at codon 1122 is replaced by leucine, an amino acid with dissimilar properties. This amino acid position is not well conserved in 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.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.010
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.69	D
Eigen	Benign	-0.24
Eigen_PC	Benign	-0.15
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.89	D
M_CAP	Benign	0.061	D
MetaRNN	Benign	0.33	T
MetaSVM	Uncertain	-0.25	T
MutationAssessor	Uncertain	2.1	M
PhyloP100		3.5
PrimateAI	Benign	0.33	T
PROVEAN	Uncertain	-2.6	D
REVEL	Uncertain	0.54
Sift	Uncertain	0.016	D
Sift4G	Benign	0.066	T
Polyphen		0.10	B
Vest4		0.42
MutPred		0.38		Loss of solvent accessibility (P = 3e-04)
MVP		0.92
ClinPred		0.93	D
GERP RS		1.6
Varity_R		0.11
gMVP		0.44
Mutation Taster		=83/17	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: rs369536711; hg19: chr16-2129638;