TSC1

Chr 9AD

TSC complex subunit 1

Also known as: LAM, TSC

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]

Primary Disease Associations & Inheritance

Focal cortical dysplasia, type II, somaticMIM #607341
LymphangioleiomyomatosisMIM #606690
Tuberous sclerosis-1MIM #191100
AD
Tuberous sclerosis-1MIM #191100
AD
5711
ClinVar variants
0
Pathogenic / LP
1.00
pLI score· haploinsufficient
11
Active trials
Clinical SummaryTSC1
Population Constraint (gnomAD)
Highly constrained gene — heterozygous loss-of-function variants are very rare in the population (pLI 1.00). One damaged copy is likely sufficient to cause disease.
📋
ClinVar Variants
5711 total variants — no pathogenic classifications of 5711 total submissions
💊
Clinical Trials
11 active or recruiting trials — potential therapeutic options may be available

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

LoF intolerant — likely haploinsufficient
LoF Constraint?LOEUF (Loss-of-function Observed/Expected Upper bound Fraction) is the upper bound of the 90% CI for LoF OE — the preferred gnomAD v4 metric. Lower = more intolerant to LoF. LOEUF < 0.35 = highly constrained.
0.12LOEUF
pLI 1.000
Z-score 6.51
OE 0.04 (0.010.12)
Highly constrained

Among the most LoF-intolerant genes (~top 3%)

Missense Constraint?Missense Z-score: standard deviations fewer missense variants observed vs. expected. Z > 3.09 (p < 0.001) = gene does not tolerate missense variation. OE missense < 0.6 is also considered constrained.
2.32Z-score
OE missense 0.74 (0.690.80)
479 obs / 644.9 exp
Mild constraint

Moderately missense-constrained (top ~2.5%)

Observed / Expected Ratios?Shaded band = 90% confidence interval. Vertical tick = point estimate. Grey threshold line = gnomAD constraint cutoff for that variant class.
LoF OE?Ratio of observed to expected LoF variants. Upper CI bound (LOEUF) ≤ 0.35 = strong LoF constraint signal.0.04 (0.010.12)
00.351.4
Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.0.74 (0.690.80)
00.61.4
Synonymous OE?Control metric — synonymous variants are largely neutral and expected near OE = 1.0. Significant deviation may indicate annotation issues.0.95
01.21.6
LoF obs/exp: 2 / 53.3Missense obs/exp: 479 / 644.9Syn Z: 0.59

ClinVar Variant Classifications

5711 submitted variants in ClinVar

Classification Summary

Protein Context — Lollipop Plot

TSC1 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Gene2Phenotype Curations

TSC1-related tuberous sclerosis

definitive
ADLoss Of FunctionAbsent Gene Product, Altered Gene Product Structure
Dev. DisordersEyeSkinCancer
G2P ↗

Gene2Phenotype curations · DECIPHER consortium patient cohort (public variants) · deciphergenomics.org

OMIM — Genotype-Phenotype Relationships

2 OMIM entries

Focal cortical dysplasia, type II, somatic

MIM #607341

Molecular basis of disorder known

Lymphangioleiomyomatosis

MIM #606690

Molecular basis of disorder known

Tuberous sclerosis-1

MIM #191100

Molecular basis of disorder known

Autosomal dominant

Tuberous sclerosis-1

MIM #191100

Molecular basis of disorder known

Autosomal dominant
Clinical Literature
Landmark / reviewRecent case evidence

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

Fallopian Tube Endometrioid AdenocarcinomaFallopian Tube High Grade Serous AdenocarcinomaOvarian Endometrioid Adenocarcinoma

Testing the Addition of Ipatasertib to the Usual Chemotherapy Treatment (Paclitaxel and Carboplatin) for Stage III or IV Epithelial Ovarian Cancer

ACTIVE NOT RECRUITING
NCT05276973Phase PHASE1National Cancer Institute (NCI)Started 2022-09-08
BiopsyCarboplatinIpatasertib
TumorTumor, SolidMetastasis

Phase 2 Basket Trial of Nab-sirolimus in Patients With Malignant Solid Tumors With Pathogenic Alterations in TSC1/TSC2 Genes (PRECISION 1)

ACTIVE NOT RECRUITING
NCT05103358Phase PHASE2Aadi Bioscience, Inc.Started 2022-02-15
nab-sirolimus
Lymphoma, Non-HodgkinMultiple MyelomaAdvanced Solid Tumors

Canadian Profiling and Targeted Agent Utilization Trial (CAPTUR)

RECRUITING
NCT03297606Phase PHASE2Canadian Cancer Trials GroupStarted 2018-03-23
OlaparibDasatinibNivolumab plus Ipilimumab
Polycythemia VeraEssential ThrombocythaemiaMyelofibrosis

Prevalence Of Germline Gene Mutations In Patients With Myeloproliferative Neoplasms With Family History

NOT YET RECRUITING
NCT06923670Phase NAFondazione Policlinico Universitario Agostino Gemelli IRCCSStarted 2025-05-21
NGS testingNGS analysis for mutations in genes involved in familial predisposition to hematological malignancies
Advanced Hepatocellular CarcinomaMetastatic Hepatocellular CarcinomaStage III Hepatocellular Carcinoma AJCC v8

Testing the Addition of an Anti-cancer Drug, Sapanisertib, to the Usual Chemotherapy Treatment (Cabozantinib) in Metastatic Liver Cell Cancer With a Change in Genes for the Protein β-Catenin, The SAPHIRE Trial

RECRUITING
NCT06811116Phase PHASE1, PHASE2National Cancer Institute (NCI)Started 2025-11-17
Biospecimen CollectionCabozantinib S-malateImaging Procedure
Epilepsy

Precision Medicine in the Treatment of Epilepsy

RECRUITING
NCT05450822Gitte Moos KnudsenStarted 2022-02-18
LevetiracetamLevetiracetam TabletsLamotrigine tablet
Advanced LymphomaAdvanced Malignant Solid NeoplasmBladder Carcinoma

Targeted Therapy Directed by Genetic Testing in Treating Patients With Advanced Refractory Solid Tumors, Lymphomas, or Multiple Myeloma (The MATCH Screening Trial)

ACTIVE NOT RECRUITING
NCT02465060Phase PHASE2National Cancer Institute (NCI)Started 2015-08-17
AdavosertibAfatinibAfatinib Dimaleate
Malignant Solid Neoplasms

Adapting Treatment to the Tumor Molecular Alterations for Patients With Advanced Solid Tumors: MyOwnSpecificTreatment

RECRUITING
NCT02029001Phase PHASE2Centre Leon BerardStarted 2014-03
Nilotinib (400 mg BID)Everolimus (10 mg QD)Sorafenib (400 mg BID)
Advanced Malignant Solid NeoplasmAnn Arbor Stage III Non-Hodgkin LymphomaAnn Arbor Stage IV Non-Hodgkin Lymphoma

Targeted Therapy Directed by Genetic Testing in Treating Pediatric Patients With Relapsed or Refractory Advanced Solid Tumors, Non-Hodgkin Lymphomas, or Histiocytic Disorders (The Pediatric MATCH Screening Trial)

ACTIVE NOT RECRUITING
NCT03155620Phase PHASE2National Cancer Institute (NCI)Started 2017-07-31
Biopsy ProcedureBiospecimen CollectionBone Marrow Aspiration and Biopsy
Lymphoma, Non-HodgkinMultiple MyelomaAdvanced Solid Tumors

TAPUR: Testing the Use of Food and Drug Administration (FDA) Approved Drugs That Target a Specific Abnormality in a Tumor Gene in People With Advanced Stage Cancer

RECRUITING
NCT02693535Phase PHASE2American Society of Clinical OncologyStarted 2016-03-14
PalbociclibSunitinibTemsirolimus
Chronic Obstructive Pulmonary Disease Exacerbation

The CATALINA Study

RECRUITING
NCT05008081Wim JanssensStarted 2022-10-25