Genetic Variant TSC1:p.Leu463PhefsTer3 (chr9-132906780-T-TA) – ACMG Classification: Pathogenic (12 pts)

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1PM2PP5_Moderate

The NM_000368.5(TSC1):c.1388dupT(p.Leu463PhefsTer3) variant causes a frameshift change. The variant allele was found at a frequency of 0.000000684 in 1,461,848 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TSC1
NM_000368.5 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 5.74

Publications

2 publications found

Variant links:

Genes affected

TSC1 (HGNC:12362): (TSC complex subunit 1) This gene is a tumor suppressor gene that encodes the growth inhibitory protein hamartin. The encoded protein interacts with and stabilizes the GTPase activating protein tuberin. This hamartin-tuberin complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. This protein also functions as a co-chaperone for Hsp90 that inhibits its ATPase activity. This protein functions as a facilitator of Hsp90-mediated folding of kinase and non-kinase clients, including TSC2 and thereby preventing their ubiquitination and proteasomal degradation. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]

TSC1 Gene-Disease associations (from GenCC):

tuberous sclerosis
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
tuberous sclerosis 1
Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, PanelApp Australia, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
lung lymphangioleiomyomatosis
Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
tuberous sclerosis complex
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

TSC1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 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;

PP5

Variant 9-132906780-T-TA is Pathogenic according to our data. Variant chr9-132906780-T-TA is described in ClinVar as Pathogenic. ClinVar VariationId is 466027.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC1	NM_000368.5 link	c.1388dupT	p.Leu463PhefsTer3	frameshift_variant	Exon 14 of 23	ENST00000298552.9	NP_000359.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC1	ENST00000298552.9 link	c.1388dupT	p.Leu463PhefsTer3	frameshift_variant	Exon 14 of 23	1	NM_000368.5	ENSP00000298552.3
TSC1	ENST00000490179.4 link	c.1388dupT	p.Leu463PhefsTer3	frameshift_variant	Exon 15 of 24	3		ENSP00000495533.2

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461848

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727226

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26134

East Asian (EAS)

AF:

0.00

AC:

AN:

39696

South Asian (SAS)

AF:

0.00

AC:

AN:

86252

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53394

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

8.99e-7

AC:

AN:

1112004

Other (OTH)

AF:

0.00

AC:

AN:

60396

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.525

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

Cov.:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Tuberous sclerosis 1

Pathogenic:1

May 25, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

While this particular variant has not been reported in the literature, loss-of-function variants in TSC1 are known to be pathogenic (PMID: 10227394, 17304050). This sequence change creates a premature translational stop signal (p.Leu463Phefs*3) in the TSC1 gene. It is expected to result in an absent or disrupted protein product. This variant is not present in population databases (ExAC no frequency). For these reasons, this variant has been classified as Pathogenic.

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

PhyloP100

5.7

Mutation Taster

=0/200

disease causing (ClinVar)

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.18

Details are displayed if max score is > 0.2

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

9-132906780-TA-TAA

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over