chr16-2088452-G-A
Variant summary
Our verdict is Likely benign. The variant received -4 ACMG points: 1P and 5B. PP3BP6BS2
The NM_000548.5(TSC2):c.5266G>A(p.Glu1756Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000868 in 1,612,638 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. E1756D) has been classified as Likely benign.
Frequency
Consequence
NM_000548.5 missense
Scores
Clinical Significance
Conservation
Publications
- tuberous sclerosisInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
- tuberous sclerosis 2Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, Ambry Genetics
- lymphangioleiomyomatosisInheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
- tuberous sclerosis complexInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
Genome browser will be placed here
ACMG classification
Our verdict: Likely_benign. The variant received -4 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000263 AC: 4AN: 152142Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.0000240 AC: 6AN: 250172 AF XY: 0.0000147 show subpopulations
GnomAD4 exome AF: 0.00000685 AC: 10AN: 1460496Hom.: 0 Cov.: 33 AF XY: 0.00000551 AC XY: 4AN XY: 726558 show subpopulations
GnomAD4 genome AF: 0.0000263 AC: 4AN: 152142Hom.: 0 Cov.: 33 AF XY: 0.0000404 AC XY: 3AN XY: 74314 show subpopulations
ClinVar
Submissions by phenotype
Tuberous sclerosis 2 Uncertain:1Benign:2
- -
- -
The TSC2 c.5266G>A p.(Glu1756Lys) missense change has a maximum subpopulation frequency of 0.009% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org). The in silico tool REVEL predicts a deleterious effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. This variant has been reported in individuals with clinical features associated with tuberous sclerosis complex (PMID: 29740858, 29778030). In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -
not provided Uncertain:1Benign:1
- -
This variant is associated with the following publications: (PMID: 29778030, 29740858) -
Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
- -
Tuberous sclerosis syndrome Uncertain:1
This missense variant replaces glutamic acid with lysine at codon 1756 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 been reported in two patients with a suspected diagnosis of tuberous sclerosis (PMID: 29778030, 29740858). This variant has been identified in 6/250172 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. -
TSC2-related disorder Uncertain:1
The TSC2 c.5266G>A variant is predicted to result in the amino acid substitution p.Glu1756Lys. This variant has been reported in individuals with clinical features consistent with tuberous sclerosis and in individuals with premature ovarian insufficiency (Zheng et al. 2018. PubMed ID: 29740858; Hesse et al. 2018. PubMed ID: 29778030; Xu et al. 2022. PubMed ID: 36229297). In vitro experimental studies showed conflicted functional evidence regarding its effect on protein function (Xu et al. 2022. PubMed ID: 36229297). This variant is reported in 0.0087% of alleles in individuals of Latino descent in gnomAD (v2), including 14 heterozygotes in the most recent release of gnomAD (v4, https://gnomad.broadinstitute.org/variant/16-2088452-G-A?dataset=gnomad_r4). Although we suspect that this variant may be benign, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
Lymphangiomyomatosis;C1846385:Isolated focal cortical dysplasia type II;C1860707:Tuberous sclerosis 2 Benign:1
- -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at