rs796053513

chr16-2080192-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP6

The NM_000548.5(TSC2):c.3425T>C(p.Leu1142Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,598 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. L1142V) 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:2 B:2
• Conservation: PhyloP100: 3.18

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 16-2080192-T-C is Benign according to our data. Variant chr16-2080192-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 207784.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TSC2	NM_000548.5	c.3425T>C	p.Leu1142Pro	missense_variant	30/42	ENST00000219476.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC2	ENST00000219476.9	c.3425T>C	p.Leu1142Pro	missense_variant	30/42	5	NM_000548.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460598 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 726592

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:1 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Dec 17, 2023	This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 1142 of the TSC2 protein (p.Leu1142Pro). 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: 207784). 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%. 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. -
Likely benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 05, 2022

The p.L1142P variant (also known as c.3425T>C), located in coding exon 29 of the TSC2 gene, results from a T to C substitution at nucleotide position 3425. The leucine at codon 1142 is replaced by proline, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Oct 01, 2014

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.069
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
Cadd	Benign	22
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.50	D;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Uncertain	0.28
Eigen_PC	Benign	0.17
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Benign	0.64	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
M_CAP	Pathogenic	0.30	D
MetaRNN	Uncertain	0.60	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.46	D
MutationAssessor	Uncertain	2.1	M;.;.;.;.;.;.;.;.;M;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.59	T
PROVEAN	Benign	-1.6	N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL	Uncertain	0.57
Sift	Benign	0.12	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G	Benign	0.17	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen		1.0	D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4		0.79
MutPred		0.25		Gain of relative solvent accessibility (P = 0.0023);.;Gain of relative solvent accessibility (P = 0.0023);.;.;.;.;Gain of relative solvent accessibility (P = 0.0023);.;Gain of relative solvent accessibility (P = 0.0023);.;.;.;.;.;
MVP		0.99
ClinPred		0.63	D
GERP RS		3.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2
Varity_R		0.20
gMVP		0.43

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

Publications

LitVar

Other links and lift over

dbSNP: rs796053513; hg19: chr16-2130193; COSMIC: COSV104587127; COSMIC: COSV104587127;