9-99142578-A-G

Position:

• chr9-99142578-A-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1 PM2 PP2 PP3_Strong PP5

The NM_004612.4(TGFBR1):​c.848A>G​(p.His283Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,778 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. H283L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TGFBR1 NM_004612.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 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 Pathogenic. Variant got 10 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_004612.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), TGFBR1. . Gene score misZ 2.7935 (greater than the threshold 3.09). Trascript score misZ 3.6468 (greater than threshold 3.09). GenCC has associacion of gene with familial thoracic aortic aneurysm and aortic dissection, Loeys-Dietz syndrome, multiple self-healing squamous epithelioma, Loeys-Dietz syndrome 1.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98
• PP5: Variant 9-99142578-A-G is Pathogenic according to our data. Variant chr9-99142578-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 477563.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TGFBR1	NM_004612.4	c.848A>G	p.His283Arg	missense_variant	5/9	ENST00000374994.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TGFBR1	ENST00000374994.9	c.848A>G	p.His283Arg	missense_variant	5/9	1	NM_004612.4	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461778 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727194

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 10, 2023

This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with TGFBR1-related conditions and thoracic aortic aneurysm and dissection (PMID: 25326635, 27879313; Invitae). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 477563). 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 expected to disrupt TGFBR1 protein function. This variant disrupts the p.His283 amino acid residue in TGFBR1. Other variant(s) that disrupt this residue have been observed in individuals with TGFBR1-related conditions (PMID: 27125181), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 283 of the TGFBR1 protein (p.His283Arg). -

Loeys-Dietz syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Sep 01, 2017

Likely pathogenicity based on finding it once in our laboratory in a 1-year-old female (deceased) with Loeys-Dietz syndrome/acute hepatic encephalopathy; father (deceased, not tested) and fraternal twin sister (has the variant) also had Loeys-Dietz syndrome. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.49	T;.;.;.
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D;D;D
M_CAP	Pathogenic	0.50	D
MetaRNN	Pathogenic	0.98	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.6	M;.;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-7.7	D;D;D;D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D;D;D;D
Sift4G	Uncertain	0.0020	D;D;D;D
Polyphen		1.0	D;D;.;.
Vest4		0.93
MutPred		0.89		Gain of helix (P = 0.1736);.;.;.;
MVP		0.98
MPC		1.8
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.99
gMVP		0.94

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: rs1064796037; hg19: chr9-101904860; COSMIC: COSV66625753; COSMIC: COSV66625753;