rs193922662

Positions:

• chr3-30672346-A-G
• chr3-30672346-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_003242.6(TGFBR2):​c.1163A>G​(p.Lys388Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,586 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:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TGFBR2 NM_003242.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.32

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]

TGFBR2 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a domain Protein kinase (size 300) in uniprot entity TGFR2_HUMAN there are 34 pathogenic changes around while only 5 benign (87%) in NM_003242.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.899

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TGFBR2	NM_003242.6	c.1163A>G	p.Lys388Arg	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.1163A>G	p.Lys388Arg	missense_variant	4/7	1	NM_003242.6	ENSP00000295754.5
TGFBR2	ENST00000359013.4	c.1238A>G	p.Lys413Arg	missense_variant	5/8	1		ENSP00000351905.4
TGFBR2	ENST00000672866.1	n.2759A>G		non_coding_transcript_exon_variant	4/7

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461586 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727080

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.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Dec 20, 2022

Variant summary: TGFBR2 c.1163A>G (p.Lys388Arg) results in a conservative amino acid change located in the kinase domain (IPR000719) of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 250540 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1163A>G in individuals affected with Loeys-Dietz Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Familial thoracic aortic aneurysm and aortic dissection Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 10, 2021

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. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C25"). This variant has not been reported in the literature in individuals with TGFBR2-related disease. ClinVar contains an entry for this variant (Variation ID: 36863). This variant is not present in population databases (ExAC no frequency). This sequence change replaces lysine with arginine at codon 388 of the TGFBR2 protein (p.Lys388Arg). The lysine residue is highly conserved and there is a small physicochemical difference between lysine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.23
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	D;.
Eigen	Uncertain	0.57
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.93	D;D
M_CAP	Uncertain	0.12	D
MetaRNN	Pathogenic	0.90	D;D
MetaSVM	Uncertain	0.67	D
MutationAssessor	Benign	0.84	L;.
PrimateAI	Pathogenic	0.79	T
PROVEAN	Uncertain	-2.7	D;D
REVEL	Pathogenic	0.85
Sift	Benign	0.091	T;T
Sift4G	Uncertain	0.054	T;D
Polyphen		0.97	D;.
Vest4		0.81
MutPred		0.76		Loss of methylation at K388 (P = 0.0115);.;
MVP		0.97
MPC		0.78
ClinPred		0.94	D
GERP RS		5.0
Varity_R		0.60
gMVP		0.63

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: rs193922662; hg19: chr3-30713838;