9-132896452-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000368.5(TSC1):​c.3278G>A​(p.Arg1093Gln) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,614,172 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1093L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

TSC1
NM_000368.5 missense

Scores

8
8
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 7.03

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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC1NM_000368.5 linkc.3278G>A p.Arg1093Gln missense_variant Exon 23 of 23 ENST00000298552.9 NP_000359.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TSC1ENST00000298552.9 linkc.3278G>A p.Arg1093Gln missense_variant Exon 23 of 23 1 NM_000368.5 ENSP00000298552.3
TSC1ENST00000490179.4 linkc.3278G>A p.Arg1093Gln missense_variant Exon 24 of 24 3 ENSP00000495533.2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152160
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251470
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461894
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00000657
AC:
1
AN:
152278
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74456
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41560
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Mar 13, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 04, 2017
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The de novo R1093Q variant in the TSC1 gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The R1093Q variant was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The R1093Q variant is a semi-conservative amino acid substitution, which may impact secondary protein structure as these residues differ in some properties. This substitution occurs at a position that is conserved across species. In silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. We interpret R1093Q as a variant of uncertain significance. -

Tuberous sclerosis 1 Uncertain:1Benign:1
Nov 07, 2021
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 20, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Tuberous sclerosis syndrome Uncertain:1
Sep 04, 2023
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces arginine with glutamine at codon 1093 of the TSC1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with TSC1-related disorders in the literature. This variant has been identified in 1/251470 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Isolated focal cortical dysplasia type II Uncertain:1
Oct 24, 2023
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

TSC1-related disorder Uncertain:1
Mar 22, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The TSC1 c.3278G>A variant is predicted to result in the amino acid substitution p.Arg1093Gln. This variant was reported in an individual with keratoconus without tuberous sclerosis and classified as a variant of uncertain significance (Bykhovskaya et al 2017. PubMed ID: 29261847). This variant is reported in 0.0033% of alleles in individuals of South Asian descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Hereditary cancer-predisposing syndrome Uncertain:1
May 10, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R1093Q variant (also known as c.3278G>A), located in coding exon 21 of the TSC1 gene, results from a G to A substitution at nucleotide position 3278. The arginine at codon 1093 is replaced by glutamine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.28
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.33
CADD
Uncertain
26
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.42
T;.;T;.;.;T;.;T;.;.;.
Eigen
Pathogenic
0.79
Eigen_PC
Pathogenic
0.77
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.95
.;D;D;D;D;.;.;.;D;D;.
M_CAP
Uncertain
0.26
D
MetaRNN
Uncertain
0.73
D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.70
D
MutationAssessor
Uncertain
2.4
M;.;M;.;.;M;.;M;.;.;.
PhyloP100
7.0
PrimateAI
Pathogenic
0.81
D
PROVEAN
Benign
-1.2
N;N;N;.;.;.;.;.;.;.;.
REVEL
Pathogenic
0.69
Sift
Pathogenic
0.0
D;D;D;.;.;.;.;.;.;.;.
Sift4G
Uncertain
0.023
D;D;D;.;.;.;.;.;.;.;.
Polyphen
1.0
D;.;D;.;.;D;.;D;.;.;.
Vest4
0.85
MutPred
0.43
Gain of ubiquitination at K1091 (P = 0.0171);.;Gain of ubiquitination at K1091 (P = 0.0171);.;.;Gain of ubiquitination at K1091 (P = 0.0171);.;Gain of ubiquitination at K1091 (P = 0.0171);.;.;.;
MVP
0.95
MPC
1.5
ClinPred
0.99
D
GERP RS
4.7
Varity_R
0.50
gMVP
0.61
Mutation Taster
=69/31
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: rs550526986; hg19: chr9-135771839; API