rs863223816

chr9-99142550-A-Cchr9-99142550-A-Gchr9-99142550-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP2 PP3

The NM_004612.4(TGFBR1):c.820A>C(p.Thr274Pro) 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T274A) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TGFBR1 NM_004612.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.32

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 8 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_004612.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr9-99142550-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 213879.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP2: Missense variant where missense usually causes diseases, TGFBR1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.794

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TGFBR1	NM_004612.4	c.820A>C	p.Thr274Pro	missense_variant	5/9	ENST00000374994.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TGFBR1	ENST00000374994.9	c.820A>C	p.Thr274Pro	missense_variant	5/9	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:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Mar 05, 2020

In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a TGFBR1-related disease. This variant has been reported to segregate with aortopathy in a single family (Invitae). This sequence change replaces threonine with proline at codon 274 of the TGFBR1 protein (p.Thr274Pro). The threonine residue is highly conserved and there is a small physicochemical difference between threonine and proline. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.23
Cadd	Pathogenic	30
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.46	T;.;.;.
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;D;D;D
M_CAP	Uncertain	0.12	D
MetaRNN	Pathogenic	0.79	D;D;D;D
MetaSVM	Uncertain	-0.28	T
MutationAssessor	Benign	1.9	L;.;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-5.8	D;D;D;D
REVEL	Pathogenic	0.65
Sift	Pathogenic	0.0	D;D;D;D
Sift4G	Uncertain	0.012	D;T;D;D
Polyphen		1.0	D;B;.;.
Vest4		0.76
MutPred		0.58		Gain of loop (P = 0.2045);.;.;.;
MVP		0.92
MPC		1.9
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.98
gMVP		0.96

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.10		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: rs863223816; hg19: chr9-101904832;