16-2084495-G-C

Variant names:

• chr16-2084495-G-C
• rs763497329
• NM_000548.5:c.4273G>C

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4 BP6 BS2

The NM_000548.5(TSC2):​c.4273G>C​(p.Gly1425Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000412 in 1,456,820 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Benign in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1425A) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:2
• Conservation: PhyloP100: 3.93
• Publications: 1 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_benign. The variant received -6 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.3792358).
• BP6: Variant 16-2084495-G-C is Benign according to our data. Variant chr16-2084495-G-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 468076.We mark this variant Likely_benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].
• BS2: High AC in GnomAdExome4 at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5	c.4273G>C	p.Gly1425Arg	missense_variant	Exon 34 of 42	ENST00000219476.9	NP_000539.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9	c.4273G>C	p.Gly1425Arg	missense_variant	Exon 34 of 42	5	NM_000548.5	ENSP00000219476.3

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 0.00000412 AC: 6 AN: 1456820 Hom.: 0 Cov.: 33 AF XY: 0.00000414 AC XY: 3 AN XY: 724594

African (AFR) AF: 0.00 AC: 0 AN: 33380

American (AMR) AF: 0.00 AC: 0 AN: 44296

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26026

East Asian (EAS) AF: 0.00 AC: 0 AN: 39500

South Asian (SAS) AF: 0.00 AC: 0 AN: 85752

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51298

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00000540 AC: 6 AN: 1110620

Other (OTH) AF: 0.00 AC: 0 AN: 60186

GnomAD4 genome Cov.: 34

Alfa AF: 0.0000565 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Tuberous sclerosis 2 Benign:2

Aug 20, 2024

Myriad Genetics, Inc.

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign. This variant has been observed at a population frequency that is significantly greater than expected given the associated disease prevalence and penetrance. -

Feb 11, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Jan 31, 2023

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 23514105) -

Hereditary cancer-predisposing syndrome Uncertain:1

Feb 17, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.G1425R variant (also known as c.4273G>C), located in coding exon 33 of the TSC2 gene, results from a G to C substitution at nucleotide position 4273. The glycine at codon 1425 is replaced by arginine, 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 v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.077
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Benign	16
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.62	D;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Benign	-0.012
Eigen_PC	Benign	-0.13
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.88	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.17	D
MetaRNN	Benign	0.38	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Uncertain	-0.054	T
MutationAssessor	Uncertain	2.2	M;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100		3.9
PrimateAI	Uncertain	0.54	T
PROVEAN	Benign	-1.8	N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL	Uncertain	0.42
Sift	Uncertain	0.0030	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G	Benign	0.38	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen		1.0	D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4		0.45
MutPred		0.20		Loss of sheet (P = 0.0228);.;.;.;.;.;.;Loss of sheet (P = 0.0228);.;.;.;.;.;.;.;
MVP		0.91
ClinPred		0.78	D
GERP RS		2.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Varity_R		0.072
gMVP		0.53
Mutation Taster		=96/4	polymorphism

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: rs763497329; hg19: chr16-2134496;