rs764028978
Variant summary
Our verdict is Likely benign. The variant received -3 ACMG points: 1P and 4B. PP3BS2
The NM_003238.6(TGFB2):c.589G>A(p.Glu197Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000192 in 1,461,866 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 Uncertain significance (★★).
Frequency
Consequence
NM_003238.6 missense
Scores
Clinical Significance
Conservation
Publications
- familial thoracic aortic aneurysm and aortic dissectionInheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
- Loeys-Dietz syndrome 4Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), PanelApp Australia, G2P
Genome browser will be placed here
ACMG classification
Our verdict: Likely_benign. The variant received -3 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| TGFB2 | NM_003238.6 | c.589G>A | p.Glu197Lys | missense_variant | Exon 3 of 7 | ENST00000366930.9 | NP_003229.1 | |
| TGFB2 | NM_001135599.4 | c.673G>A | p.Glu225Lys | missense_variant | Exon 4 of 8 | NP_001129071.1 | ||
| TGFB2 | NR_138148.2 | n.1955G>A | non_coding_transcript_exon_variant | Exon 3 of 7 | ||||
| TGFB2 | NR_138149.2 | n.2039G>A | non_coding_transcript_exon_variant | Exon 4 of 8 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| TGFB2 | ENST00000366930.9 | c.589G>A | p.Glu197Lys | missense_variant | Exon 3 of 7 | 1 | NM_003238.6 | ENSP00000355897.4 | ||
| TGFB2 | ENST00000366929.4 | c.673G>A | p.Glu225Lys | missense_variant | Exon 4 of 8 | 1 | ENSP00000355896.4 | |||
| TGFB2 | ENST00000479322.1 | n.35G>A | non_coding_transcript_exon_variant | Exon 1 of 5 | 3 | |||||
| TGFB2 | ENST00000488793.1 | n.253G>A | non_coding_transcript_exon_variant | Exon 3 of 3 | 3 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD2 exomes AF: 0.00000796 AC: 2AN: 251248 AF XY: 0.0000147 show subpopulations
GnomAD4 exome AF: 0.0000192 AC: 28AN: 1461866Hom.: 0 Cov.: 31 AF XY: 0.0000234 AC XY: 17AN XY: 727236 show subpopulations
Age Distribution
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
Loeys-Dietz syndrome 4 Uncertain:3
Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with Loeys-Dietz syndrome 4 (MIM#614816). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from glutamic acid to lysine. (I) 0251 - This variant is heterozygous. (I) 0302 - Variant is present in gnomAD (v2) <0.001 for a dominant condition (2 heterozygotes, 0 homozygotes). (SP) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0600 - Variant is located in the annotated TGF-beta propeptide domain (DECIPHER). (I) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0809 - Previous evidence of pathogenicity for this variant is inconclusive. This variant has been reported twice as a VUS (ClinVar). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 197 of the TGFB2 protein (p.Glu197Lys). This variant is present in population databases (rs764028978, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with TGFB2-related conditions. ClinVar contains an entry for this variant (Variation ID: 295490). 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 TGFB2 protein function with a negative predictive value of 95%. 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. -
Familial thoracic aortic aneurysm and aortic dissection Uncertain:1
The p.E197K variant (also known as c.589G>A), located in coding exon 3 of the TGFB2 gene, results from a G to A substitution at nucleotide position 589. The glutamic acid at codon 197 is replaced by lysine, an amino acid with 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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at