rs768423844

Variant names:

• chr14-75963334-T-G
• rs768423844
• NM_003239.5:c.908A>C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM1 PP3

The NM_003239.5(TGFB3):​c.908A>C​(p.Asp303Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,822 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D303H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: TGFB3 NM_003239.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 8.02
• Publications: 0 publications found

Genes affected

TGFB3 (HGNC:11769): (transforming growth factor beta 3) This gene encodes a secreted ligand of the TGF-beta (transforming growth factor-beta) superfamily of proteins. Ligands of this family bind various TGF-beta receptors leading to recruitment and activation of SMAD family transcription factors that regulate gene expression. The encoded preproprotein is proteolytically processed to generate a latency-associated peptide (LAP) and a mature peptide, and is found in either a latent form composed of a mature peptide homodimer, a LAP homodimer, and a latent TGF-beta binding protein, or in an active form consisting solely of the mature peptide homodimer. The mature peptide may also form heterodimers with other TGF-beta family members. This protein is involved in embryogenesis and cell differentiation, and may play a role in wound healing. Mutations in this gene are a cause of aortic aneurysms and dissections, as well as familial arrhythmogenic right ventricular dysplasia 1. [provided by RefSeq, Aug 2016]

IFT43 (HGNC:29669): (intraflagellar transport 43) This gene encodes a subunit of the intraflagellar transport complex A (IFT-A). IFT-A is a multiprotein complex that plays an important role in cilia assembly and maintenance by mediating retrograde ciliary transport. Mutations in this gene are a cause of cranioectodermal dysplasia-3 (CED3), also known as Sensenbrenner syndrome. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Dec 2011]

IFT43 Gene-Disease associations (from GenCC):

• cranioectodermal dysplasia 3

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• short-rib thoracic dysplasia 18 with polydactyly

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• cranioectodermal dysplasia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• ciliopathy

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics
• retinitis pigmentosa 81

  Inheritance: AR, Unknown Classification: LIMITED Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 15 uncertain in NM_003239.5
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.829

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TGFB3	NM_003239.5	c.908A>C	p.Asp303Ala	missense_variant	Exon 5 of 7	ENST00000238682.8	NP_003230.1
TGFB3	NM_001329939.2	c.908A>C	p.Asp303Ala	missense_variant	Exon 6 of 8		NP_001316868.1
TGFB3	NM_001329938.2	c.908A>C	p.Asp303Ala	missense_variant	Exon 5 of 5		NP_001316867.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TGFB3	ENST00000238682.8	c.908A>C	p.Asp303Ala	missense_variant	Exon 5 of 7	1	NM_003239.5	ENSP00000238682.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.0000159 AC: 4 AN: 251378 AF XY: 0.0000221

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000352

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461822 Hom.: 0 Cov.: 33 AF XY: 0.00000688 AC XY: 5 AN XY: 727192

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5756

European-Non Finnish (NFE) AF: 0.00000630 AC: 7 AN: 1111966

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.0000247 AC: 3

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Arrhythmogenic right ventricular dysplasia 1;C3810012:Rienhoff syndrome Uncertain:1

Jul 20, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Rienhoff syndrome Uncertain:1

Jun 11, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has not been reported in the literature in individuals with TGFB3-related disease. 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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant is present in population databases (rs768423844, ExAC 0.004%). This sequence change replaces aspartic acid with alanine at codon 303 of the TGFB3 protein (p.Asp303Ala). The aspartic acid residue is highly conserved and there is a moderate physicochemical difference between aspartic acid and alanine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.70
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.13
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.89	D;.
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Benign	0.85	D;D
M_CAP	Pathogenic	0.32	D
MetaRNN	Pathogenic	0.83	D;D
MetaSVM	Uncertain	0.41	D
MutationAssessor	Uncertain	2.3	M;M
PhyloP100		8.0
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-4.9	D;D
REVEL	Pathogenic	0.79
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.012	D;D
Polyphen		1.0	D;.
Vest4		0.71
MutPred		0.57		Gain of MoRF binding (P = 0.0432);Gain of MoRF binding (P = 0.0432);
MVP		0.68
MPC		1.8
ClinPred		0.98	D
GERP RS		5.4
Varity_R		0.86
gMVP		0.89
Mutation Taster		=26/74	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs768423844; hg19: chr14-76429677;