rs118203645

Variant names:

• chr9-132903746-CAT-C
• rs118203645
• NM_000368.5:c.2111_2112delAT

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000368.5(TSC1):​c.2111_2112delAT​(p.Tyr704fs) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TSC1 NM_000368.5 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:6 O:1
• Conservation: PhyloP100: 5.06
• Publications: 4 publications found

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

ACMG classification

Our verdict: Pathogenic. The variant received 18 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 9-132903746-CAT-C is Pathogenic according to our data. Variant chr9-132903746-CAT-C is described in ClinVar as Pathogenic. ClinVar VariationId is 48905.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC1	NM_000368.5	c.2111_2112delAT	p.Tyr704fs	frameshift_variant	Exon 17 of 23	ENST00000298552.9	NP_000359.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC1	ENST00000298552.9	c.2111_2112delAT	p.Tyr704fs	frameshift_variant	Exon 17 of 23	1	NM_000368.5	ENSP00000298552.3
TSC1	ENST00000490179.4	c.2111_2112delAT	p.Tyr704fs	frameshift_variant	Exon 18 of 24	3		ENSP00000495533.2

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Tuberous sclerosis 1 Pathogenic:3

Nov 07, 2021

Genome-Nilou Lab

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 30, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Tyr704*) in the TSC1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in TSC1 are known to be pathogenic (PMID: 10227394, 17304050). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individuals with tuberous sclerosis complex (PMID: 9242607, 15595939, 26540169). This variant is also known as 2332delAT. ClinVar contains an entry for this variant (Variation ID: 48905). For these reasons, this variant has been classified as Pathogenic. -

-

Oasi Research Institute-IRCCS

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

The genomic variant c.2111_2112delAT is a frameshift mutation resulting from the deletion of two nucleotides.This variant creates a premature translational stop signal and is expected to result in a protein truncation or nonsense-mediated decay. ACMG criteria: PVS1 (LOF), PP4 (phenotype match), PM2 (absent from controls), PP3 (in silico evidence), PS4 (affected individuals) = Pathogenic. Based on the evidence outlined above, the variant was classified as Pathogenic. -

not provided Pathogenic:1

Mar 07, 2022

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 12436247, 26540169, 17304050, 9803264, 15595939, 10363127, 29500070, 32647919, 9242607) -

Isolated focal cortical dysplasia type II Pathogenic:1

Jun 13, 2022

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Pathogenic:1

Jun 11, 2025

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2111_2112delAT pathogenic mutation, located in coding exon 15 of the TSC1 gene, results from a deletion of two nucleotides at nucleotide positions 2111 to 2112, causing a translational frameshift with a predicted alternate stop codon (p.Y704*). This variant was reported in individual(s) with features consistent with tuberous sclerosis complex (TSC) (van Slegtenhorst M et al. Science, 1997 Aug;277:805-8; Ali M et al. Acta Neurol Scand, 2005 Jan;111:54-63; Tyburczy ME et al. PLoS Genet, 2015 Nov;11:e1005637; Papadopoulou A et al. Eur J Paediatr Neurol, 2018 May;22:419-426; Ambry internal data). Note, this variant is also referred to as 2332delAT in the literature. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Tuberous sclerosis syndrome Other:1

-

Tuberous sclerosis database (TSC1)

Significance: not provided

Review Status: no classification provided

Collection Method: curation

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.1
Mutation Taster		=0/200	disease causing (ClinVar)

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: rs118203645; hg19: chr9-135779133; COSMIC: COSV53773140;