rs1555438692

Variant names:

• chr16-2086843-G-A
• rs1555438692
• NM_000548.5:c.4961G>A

Your query was ambiguous. Multiple possible variants found:

• chr16-2086843-G-A
• chr16-2086843-G-C
• chr16-2086843-G-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_000548.5(TSC2):​c.4961G>A​(p.Gly1654Asp) variant causes a missense change. The variant allele was found at a frequency of 0.000000689 in 1,450,948 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. G1654S) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.82
• 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 14 uncertain in NM_000548.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.877

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5	c.4961G>A	p.Gly1654Asp	missense_variant	Exon 38 of 42	ENST00000219476.9	NP_000539.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9	c.4961G>A	p.Gly1654Asp	missense_variant	Exon 38 of 42	5	NM_000548.5	ENSP00000219476.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1450948 Hom.: 0 Cov.: 31 AF XY: 0.00000139 AC XY: 1 AN XY: 721070

African (AFR) AF: 0.00 AC: 0 AN: 33210

American (AMR) AF: 0.00 AC: 0 AN: 43576

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25972

East Asian (EAS) AF: 0.00 AC: 0 AN: 39140

South Asian (SAS) AF: 0.00 AC: 0 AN: 84888

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51370

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5152

European-Non Finnish (NFE) AF: 9.03e-7 AC: 1 AN: 1107712

Other (OTH) AF: 0.00 AC: 0 AN: 59928

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:1

Oct 26, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 1654 of the TSC2 protein (p.Gly1654Asp). 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: 2184095). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.40
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.22
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D;.;.;.;.;.;.;.;.;.;.;.;D;.;D
Eigen	Uncertain	0.33
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.90	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.38	D
MetaRNN	Pathogenic	0.88	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.73	D
MutationAssessor	Benign	1.1	L;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100		6.8
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-5.2	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
REVEL	Pathogenic	0.76
Sift	Benign	0.20	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G	Benign	0.20	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen		1.0	D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4		0.61
MutPred		0.63		Gain of solvent accessibility (P = 0.0638);.;.;.;.;.;.;.;.;.;.;.;.;.;.;
MVP		0.89
ClinPred		0.91	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.71
gMVP		0.79
Mutation Taster		=32/68	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: rs1555438692; hg19: chr16-2136844;