16-2071553-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 5P and 4B. PM1PM5PP3BS2

The NM_000548.5(TSC2):​c.1883G>A​(p.Arg628His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000229 in 1,613,448 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. R628C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

TSC2
NM_000548.5 missense

Scores

7
6
6

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 9.66
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]

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 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, 15 uncertain in NM_000548.5
PM5
Other missense variant is known to change same aminoacid residue: Variant chr16-2071552-C-G is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.801
BS2
High AC in GnomAdExome4 at 34 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
TSC2NM_000548.5 linkuse as main transcriptc.1883G>A p.Arg628His missense_variant 18/42 ENST00000219476.9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
TSC2ENST00000219476.9 linkuse as main transcriptc.1883G>A p.Arg628His missense_variant 18/425 NM_000548.5 P49815-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152188
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000399
AC:
1
AN:
250494
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135730
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 SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000233
AC:
34
AN:
1461260
Hom.:
0
Cov.:
32
AF XY:
0.0000193
AC XY:
14
AN XY:
726952
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000297
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152188
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74344
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000441
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000756
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:1Benign:1
Uncertain significance, criteria provided, single submitterclinical testingGenome-Nilou LabNov 07, 2021- -
Likely benign, criteria provided, single submitterclinical testingInvitaeOct 25, 2023- -
Tuberous sclerosis syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAll of Us Research Program, National Institutes of HealthOct 27, 2023This missense variant replaces arginine with histidine at codon 628 of the TSC2 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 was reported in an individual affected with tuberous sclerosis complex (PMID: 35918040). This variant has been identified in 2/281880 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. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGeneDxJul 27, 2020In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -
Hereditary cancer-predisposing syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsAug 05, 2023The p.R628H variant (also known as c.1883G>A), located in coding exon 17 of the TSC2 gene, results from a G to A substitution at nucleotide position 1883. The arginine at codon 628 is replaced by histidine, an amino acid with highly similar properties. This alteration was identified in an individual with a clinical diagnosis of tuberous sclerosis complex (Ng SY et al. Eur J Med Genet, 2022 Oct;65:104573). 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
0.29
BayesDel_addAF
Pathogenic
0.28
D
BayesDel_noAF
Pathogenic
0.26
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.43
T;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen
Uncertain
0.65
Eigen_PC
Pathogenic
0.70
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.33
D
MetaRNN
Pathogenic
0.80
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.15
D
MutationAssessor
Benign
1.2
L;.;.;.;L;L;.;.;.;L;.;L;.;.;.
MutationTaster
Benign
1.0
D;D;D;D;D;D;D
PrimateAI
Uncertain
0.76
T
PROVEAN
Benign
-0.27
N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL
Uncertain
0.64
Sift
Benign
0.39
T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G
Benign
0.26
T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen
1.0
D;.;.;.;D;D;.;.;D;D;.;.;.;.;.
Vest4
0.91
MutPred
0.59
Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);.;Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);.;Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);Loss of helix (P = 0.0626);.;
MVP
0.93
ClinPred
0.81
D
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.15
gMVP
0.74

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs774895427; hg19: chr16-2121554; COSMIC: COSV54778087; COSMIC: COSV54778087; API