rs1060500943

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1PM2

The NM_000548.5(TSC2):​c.907C>A​(p.Leu303Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000691 in 1,447,392 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L303V) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

3
12
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 2.53

Publications

1 publications found
Variant links:
Genes affected
TSC2 (HGNC:12363): (TSC complex subunit 2) This gene is a tumor suppressor gene that encodes the growth inhibitory protein tuberin. Tuberin interacts with hamartin to form the TSC protein complex which functions in the control of cell growth. This TSC protein complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]
TSC2 Gene-Disease associations (from GenCC):
  • tuberous sclerosis
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • tuberous sclerosis 2
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, Ambry Genetics
  • 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 4 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 10 benign, 35 uncertain in NM_000548.5
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC2NM_000548.5 linkc.907C>A p.Leu303Ile missense_variant Exon 10 of 42 ENST00000219476.9 NP_000539.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TSC2ENST00000219476.9 linkc.907C>A p.Leu303Ile missense_variant Exon 10 of 42 5 NM_000548.5 ENSP00000219476.3

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.91e-7
AC:
1
AN:
1447392
Hom.:
0
Cov.:
32
AF XY:
0.00000139
AC XY:
1
AN XY:
718534
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33410
American (AMR)
AF:
0.00
AC:
0
AN:
42234
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25744
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39396
South Asian (SAS)
AF:
0.00
AC:
0
AN:
83640
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52364
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5724
European-Non Finnish (NFE)
AF:
9.05e-7
AC:
1
AN:
1104968
Other (OTH)
AF:
0.00
AC:
0
AN:
59912
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Tuberous sclerosis syndrome Uncertain:1
Dec 13, 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 leucine with isoleucine at codon 303 of the TSC2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with tuberous sclerosis complex in the literature. This variant has not been identified 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. -

Tuberous sclerosis 2 Uncertain:1
Oct 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt TSC2 protein function. ClinVar contains an entry for this variant (Variation ID: 406034). This variant has not been reported in the literature in individuals affected with TSC2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces leucine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 303 of the TSC2 protein (p.Leu303Ile). -

Hereditary cancer-predisposing syndrome Uncertain:1
Jul 08, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.L303I variant (also known as c.907C>A), located in coding exon 9 of the TSC2 gene, results from a C to A substitution at nucleotide position 907. The leucine at codon 303 is replaced by isoleucine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. 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
Uncertain
0.52
BayesDel_addAF
Pathogenic
0.17
D
BayesDel_noAF
Uncertain
0.010
CADD
Uncertain
25
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.49
T;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen
Uncertain
0.54
Eigen_PC
Uncertain
0.55
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.87
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Uncertain
0.16
D
MetaRNN
Uncertain
0.47
T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Uncertain
-0.28
T
MutationAssessor
Benign
2.0
M;.;.;.;M;M;.;.;.;M;.;M;.;.;.
PhyloP100
2.5
PrimateAI
Pathogenic
0.80
T
PROVEAN
Benign
-1.6
N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL
Benign
0.25
Sift
Pathogenic
0.0
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G
Uncertain
0.030
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Polyphen
0.99
D;.;.;.;D;D;.;.;D;P;.;.;.;.;.
Vest4
0.66
MutPred
0.30
Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);.;Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);.;Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);Gain of MoRF binding (P = 0.11);.;
MVP
0.66
ClinPred
0.96
D
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.78
gMVP
0.31
Mutation Taster
=67/33
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: rs1060500943; hg19: chr16-2108806; API