NM_000548.5:c.1033C>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 5P and 1B. PM1PM2PP3BP6

The NM_000548.5(TSC2):​c.1033C>T​(p.Leu345Phe) variant causes a missense change. The variant allele was found at a frequency of 0.0000031 in 1,614,012 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 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. L345R) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

8
9
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:3O:1

Conservation

PhyloP100: 3.92

Publications

6 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 7 benign, 32 uncertain in NM_000548.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.805
BP6
Variant 16-2060727-C-T is Benign according to our data. Variant chr16-2060727-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 65196.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TSC2NM_000548.5 linkc.1033C>T p.Leu345Phe missense_variant Exon 11 of 42 ENST00000219476.9 NP_000539.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TSC2ENST00000219476.9 linkc.1033C>T p.Leu345Phe missense_variant Exon 11 of 42 5 NM_000548.5 ENSP00000219476.3

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152170
Hom.:
0
Cov.:
33
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:
0.000193
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
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251368
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:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461842
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
727224
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:
0.0000504
AC:
2
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53378
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1112004
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
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:
0.00000657
AC:
1
AN:
152170
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74324
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41438
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
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

Genome 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
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:3Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Tuberous sclerosis 2 Benign:3
Nov 07, 2021
Genome-Nilou Lab
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 13, 2025
Myriad Genetics, Inc.
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign. This variant has been observed at a population frequency that is significantly greater than expected given the associated disease prevalence and penetrance. -

Nov 27, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Tuberous sclerosis syndrome Uncertain:1Other:1
Nov 30, 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 phenylalanine at codon 345 of the TSC2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 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 TSC2-related disorders in the literature. This variant has been identified in 3/282760 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. -

-
Tuberous sclerosis database (TSC2)
Significance:not provided
Review Status:no classification provided
Collection Method:curation

- -

Lymphangiomyomatosis;C1846385:Isolated focal cortical dysplasia type II;C1860707:Tuberous sclerosis 2 Uncertain:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The TSC2 p.Leu145Phe variant was identified in dbSNP (ID: rs397515146) as “With Uncertain significance allele”. The c.433C>T variant was identified in ClinVar and Clinvitae, and classified by Invitae as uncertain significance for Tuberous Sclerosis 2. The variant was identified in LOVD 3.0 as benign, and was reported in LOVD 2.0 in a patient diagnosed with Tuberous Sclerosis who was also found to have a TSC2 frameshift c.957_958del variant (Sancak_2005_PMID: 15798777) increasing the likelihood the c.433C>T variant may not have clinical significance. The variant was not identified in the Cosmic or MutDB databases. The variant was identified in control databases in 3 of 282760 chromosomes at a frequency of 0.000011 (Genome Aggregation Database Feb 27, 2017). The variant was only observed in one population: East Asian in 3 of 19952 chromosomes (freq: 0.00015), but not in the African, Latino, Ashkenazi Jewish, European (Finnish), European (non-Finnish), Other and South Asian populations. The p.Leu145 residue is not conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, and MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.90
BayesDel_addAF
Uncertain
0.13
D
BayesDel_noAF
Pathogenic
0.18
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.88
D;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen
Uncertain
0.30
Eigen_PC
Benign
0.18
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.89
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.51
D
MetaRNN
Pathogenic
0.81
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.12
D
MutationAssessor
Uncertain
2.6
M;.;.;.;M;M;.;.;.;M;.;M;.;.;.
PhyloP100
3.9
PrimateAI
Uncertain
0.71
T
PROVEAN
Uncertain
-3.5
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
REVEL
Pathogenic
0.70
Sift
Pathogenic
0.0
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G
Pathogenic
0.0
D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Polyphen
1.0
D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4
0.91
MutPred
0.58
Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);.;Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);.;Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);Gain of methylation at K348 (P = 0.1031);.;
MVP
0.80
ClinPred
0.97
D
GERP RS
3.6
Varity_R
0.69
gMVP
0.71
Mutation Taster
=51/49
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.33
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.33
Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs397515146; hg19: chr16-2110728; API