chr9-132911522-TAAC-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 1P and 1B. PM4_SupportingBP6

The NM_000368.5(TSC1):​c.957_959delGTT​(p.Leu320del) variant causes a disruptive inframe deletion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,611,690 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. L319L) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 29)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

TSC1
NM_000368.5 disruptive_inframe_deletion

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:2

Conservation

PhyloP100: 1.47

Publications

1 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM4
Nonframeshift variant in NON repetitive region in NM_000368.5. Strenght limited to Supporting due to length of the change: 1aa.
BP6
Variant 9-132911522-TAAC-T is Benign according to our data. Variant chr9-132911522-TAAC-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 411287.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=4, Likely_benign=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC1NM_000368.5 linkc.957_959delGTT p.Leu320del disruptive_inframe_deletion Exon 10 of 23 ENST00000298552.9 NP_000359.1 Q92574-1Q86WV8X5D9D2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TSC1ENST00000298552.9 linkc.957_959delGTT p.Leu320del disruptive_inframe_deletion Exon 10 of 23 1 NM_000368.5 ENSP00000298552.3 Q92574-1
TSC1ENST00000490179.4 linkc.957_959delGTT p.Leu320del disruptive_inframe_deletion Exon 11 of 24 3 ENSP00000495533.2 A0A2R8Y6S8

Frequencies

GnomAD3 genomes
AF:
0.0000200
AC:
3
AN:
149860
Hom.:
0
Cov.:
29
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000202
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461830
Hom.:
0
AF XY:
0.00000275
AC XY:
2
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111964
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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
AF:
0.0000200
AC:
3
AN:
149860
Hom.:
0
Cov.:
29
AF XY:
0.00
AC XY:
0
AN XY:
72904
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
40458
American (AMR)
AF:
0.000202
AC:
3
AN:
14852
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5064
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4782
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10108
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
308
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67840
Other (OTH)
AF:
0.00
AC:
0
AN:
2070
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.542
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000756

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2
Apr 19, 2021
Sema4, Sema4
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Jul 25, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.957_959delGTT variant (also known as p.L320del) is located in coding exon 8 of the TSC1 gene. This variant results from an in-frame GTT deletion at nucleotide positions 957 to 959. This results in the in-frame deletion of a leucine at codon 320. This nucleotide region is not well conserved in available vertebrate species. In addition, this alteration is predicted to be neutral by in silico analysis (Choi Y et al. PLoS ONE. 2012; 7(10):e46688). Based on the available evidence, the clinical significance of this variant remains unclear. -

not provided Uncertain:1Benign:1
Nov 06, 2019
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The TSC1 c.957_959delGTT; p.Leu320del variant (rs755655903), also known as 954_956GTT[1], is reported in ClinVar (Variation ID: 411287). This variant is absent from general population databases (Exome Variant Server, Genome Aggregation Database), indicating it is not a common polymorphism. This variant deletes a single leucine residue leaving the rest of the protein in-frame. Due to limited information, the clinical significance of this variant is uncertain at this time. -

Feb 02, 2023
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

See Variant Classification Assertion Criteria. -

not specified Uncertain:1
Apr 08, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: TSC1 c.957_959delGTT (p.Leu320del) results in an in-frame deletion that is predicted to remove one amino acids from the encoded protein. The variant was absent in 251324 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.957_959delGTT in individuals affected with Tuberous Sclerosis Complex and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 411287). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Seizure Uncertain:1
Aug 11, 2017
Clinical Molecular Genetics Laboratory, Johns Hopkins All Children's Hospital
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Tuberous sclerosis 1 Benign:1
Dec 12, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
1.5
Mutation Taster
=79/21
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

Publications

Other links and lift over

dbSNP: rs755655903; hg19: chr9-135786909; API