9-99137895-C-T

Position:

• chr9-99137895-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_004612.4(TGFBR1):​c.611C>T​(p.Thr204Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: TGFBR1 NM_004612.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 7.86

Genes affected

TGFBR1 (HGNC:11772): (transforming growth factor beta receptor 1) The protein encoded by this gene forms a heteromeric complex with type II TGF-beta receptors when bound to TGF-beta, transducing the TGF-beta signal from the cell surface to the cytoplasm. The encoded protein is a serine/threonine protein kinase. Mutations in this gene have been associated with Loeys-Dietz aortic aneurysm syndrome (LDAS). Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 14 uncertain in NM_004612.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, TGFBR1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.845

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TGFBR1	NM_004612.4	c.611C>T	p.Thr204Ile	missense_variant	4/9	ENST00000374994.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TGFBR1	ENST00000374994.9	c.611C>T	p.Thr204Ile	missense_variant	4/9	1	NM_004612.4	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	May 07, 2023	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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on TGFBR1 protein function. ClinVar contains an entry for this variant (Variation ID: 264166). This missense change has been observed in individuals with aortic dissections (PMID: 23064905; Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 204 of the TGFBR1 protein (p.Thr204Ile). -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jul 21, 2015	The p.T204I variant (also known as c.611C>T), located in coding exon 4 of the TGFBR1 gene, results from a C to T substitution at nucleotide position 611. The threonine at codon 204 is replaced by isoleucine, an amino acid with similar properties. This variant was reported in one patient with medial fibroplasia and multi-vessel dissections (Poloskey et al.Vasc Med. 2012;17(6):371-8). This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. 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 clinical data on this variant is limited at this time, its clinical significance is unclear. -

Loeys-Dietz syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Nov 30, 2023

- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Mar 02, 2021

Not observed in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Reported in ClinVar as a variant of uncertain significance (ClinVar Variant ID# 264166; Landrum et al., 2016); This variant is associated with the following publications: (PMID: 7774578, 23064905) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	D;.;.;D;.
Eigen	Uncertain	0.68
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.84	T;T;T;D;T
M_CAP	Uncertain	0.23	D
MetaRNN	Pathogenic	0.85	D;D;D;D;D
MetaSVM	Uncertain	0.71	D
MutationAssessor	Benign	1.9	M;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.87	D
PROVEAN	Uncertain	-3.5	D;D;D;D;D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0010	D;D;D;D;D
Sift4G	Uncertain	0.0040	D;D;D;D;D
Polyphen		0.99	D;D;.;.;.
Vest4		0.88
MutPred		0.46		Loss of sheet (P = 0.0817);.;.;.;.;
MVP		0.96
MPC		3.4
ClinPred		0.98	D
GERP RS		5.6
Varity_R		0.94
gMVP		0.90

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

Other links and lift over

dbSNP: rs886039068; hg19: chr9-101900177;