3-30672096-C-T

Position:

• chr3-30672096-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP3_Moderate PP5

The ENST00000295754.10(TGFBR2):​c.913C>T​(p.Leu305Phe) 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L305H) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TGFBR2 ENST00000295754.10 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:1
• Conservation: PhyloP100: 7.90

Genes affected

TGFBR2 (HGNC:11773): (transforming growth factor beta receptor 2) The protein encoded by this gene is a transmembrane protein that has a protein kinase domain, forms a heterodimeric complex with TGF-beta receptor type-1, and binds TGF-beta. This receptor/ligand complex phosphorylates proteins, which then enter the nucleus and regulate the transcription of genes related to cell proliferation, cell cycle arrest, wound healing, immunosuppression, and tumorigenesis. Mutations in this gene have been associated with Marfan Syndrome, Loeys-Deitz Aortic Aneurysm Syndrome, and the development of various types of tumors. Alternatively spliced transcript variants encoding different isoforms have been characterized. [provided by RefSeq, Aug 2017]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in ENST00000295754.10
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr3-30672097-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2747583.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.932
• PP5: Variant 3-30672096-C-T is Pathogenic according to our data. Variant chr3-30672096-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 449834.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Pathogenic=2, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TGFBR2	NM_003242.6	c.913C>T	p.Leu305Phe	missense_variant	4/7	ENST00000295754.10	NP_003233.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TGFBR2	ENST00000295754.10	c.913C>T	p.Leu305Phe	missense_variant	4/7	1	NM_003242.6	ENSP00000295754	P1
TGFBR2	ENST00000359013.4	c.988C>T	p.Leu330Phe	missense_variant	5/8	1		ENSP00000351905
TGFBR2	ENST00000672866.1	n.2509C>T		non_coding_transcript_exon_variant	4/7

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Apr 13, 2021	The p.L305F pathogenic mutation (also known as c.913C>T), located in coding exon 4 of the TGFBR2 gene, results from a C to T substitution at nucleotide position 913. The leucine at codon 305 is replaced by phenylalanine, an amino acid with highly similar properties. This variant has been detected in two de novo cases with findings consistent with Loeys-Dietz syndrome (Ambry internal data; Kasar T et al. Anatol J Cardiol, 2018 Jan;19:74-77). Based on internal structural analysis, this variant is anticipated to result in a significant decrease in structural stability and ligand binding (Tebben AJ et al. Acta Crystallogr D Struct Biol, 2016 05;72:658-74). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Nov 13, 2021	For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Leu305 amino acid residue in TGFBR2. Other variant(s) that disrupt this residue have been determined to be pathogenic (Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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 TGFBR2 protein function. ClinVar contains an entry for this variant (Variation ID: 449834). This missense change has been observed in individual(s) with Loeys-Dietz syndrome (PMID: 29339704). In at least one individual the variant was observed to be de novo. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces leucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 305 of the TGFBR2 protein (p.Leu305Phe). -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Aug 23, 2022

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 29339704) -

Malignant tumor of esophagus;C1860896:Colorectal cancer, hereditary nonpolyposis, type 6;C2674574:Loeys-Dietz syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 31, 2018

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Uncertain	25
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.96	D;.
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.95	D;D
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.93	D;D
MetaSVM	Uncertain	0.069	D
MutationAssessor	Uncertain	2.3	M;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.79	T
PROVEAN	Uncertain	-3.6	D;D
REVEL	Pathogenic	0.72
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.0050	D;D
Polyphen		1.0	D;.
Vest4		0.84
MutPred		0.80		Gain of methylation at K300 (P = 0.1652);.;
MVP		0.87
MPC		1.5
ClinPred		0.99	D
GERP RS		5.0
Varity_R		0.98
gMVP		0.78

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: rs1553630171; hg19: chr3-30713588;