16-2084303-C-T

Variant names:

• chr16-2084303-C-T
• rs560831385
• NM_000548.5:c.4081C>T

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP3

The NM_000548.5(TSC2):​c.4081C>T​(p.Arg1361*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,366 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 (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TSC2 NM_000548.5 stop_gained
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.995
• Publications: 3 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 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

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.4081C>T	p.Arg1361*	stop_gained	Exon 34 of 42	NP_000539.2
	TSC2	NM_001406663.1		c.4078C>T	p.Arg1360*	stop_gained	Exon 34 of 42	NP_001393592.1
	TSC2	NM_001114382.3		c.4012C>T	p.Arg1338*	stop_gained	Exon 33 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.4081C>T	p.Arg1361*	stop_gained	Exon 34 of 42	ENSP00000219476.3
	TSC2	ENST00000350773.9	TSL:1	c.4012C>T	p.Arg1338*	stop_gained	Exon 33 of 41	ENSP00000344383.4
	TSC2	ENST00000401874.7	TSL:1	c.3880C>T	p.Arg1294*	stop_gained	Exon 32 of 40	ENSP00000384468.2

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460366 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 726446

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44706

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86220

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52082

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111914

Other (OTH) AF: 0.00 AC: 0 AN: 60372

GnomAD4 genome Cov.: 34

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Hereditary cancer-predisposing syndrome (1)
-	1	-	Tuberous sclerosis 2 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.30
CADD	Pathogenic	44
DANN	Uncertain	0.99
Eigen	Uncertain	0.20
Eigen_PC	Benign	-0.084
FATHMM_MKL	Benign	0.73	D
PhyloP100		0.99
Vest4		0.89
GERP RS		1.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.80		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.80		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs560831385; hg19: chr16-2134304; COSMIC: COSV105862592;