rs1553905957

Positions:

• chr4-54285384-A-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_006206.6(PDGFRA):​c.2337A>C​(p.Lys779Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign 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. K779E) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: PDGFRA NM_006206.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.491

Genes affected

PDGFRA (HGNC:8803): (platelet derived growth factor receptor alpha) This gene encodes a cell surface tyrosine kinase receptor for members of the platelet-derived growth factor family. These growth factors are mitogens for cells of mesenchymal origin. The identity of the growth factor bound to a receptor monomer determines whether the functional receptor is a homodimer or a heterodimer, composed of both platelet-derived growth factor receptor alpha and beta polypeptides. Studies suggest that this gene plays a role in organ development, wound healing, and tumor progression. Mutations in this gene have been associated with idiopathic hypereosinophilic syndrome, somatic and familial gastrointestinal stromal tumors, and a variety of other cancers. [provided by RefSeq, Mar 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), PDGFRA. . Gene score misZ 1.9401 (greater than the threshold 3.09). Trascript score misZ 3.4078 (greater than threshold 3.09). GenCC has associacion of gene with congenital heart disease, polyps, multiple and recurrent inflammatory fibroid, gastrointestinal, gastrointestinal stromal tumor, isolated cleft palate.
• BP4: Computational evidence support a benign effect (MetaRNN=0.1199781).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PDGFRA	NM_006206.6	c.2337A>C	p.Lys779Asn	missense_variant	17/23	ENST00000257290.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PDGFRA	ENST00000257290.10	c.2337A>C	p.Lys779Asn	missense_variant	17/23	1	NM_006206.6	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 20

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Gastrointestinal stromal tumor Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 17, 2023

This variant is not present in population databases (gnomAD no frequency). This sequence change replaces lysine, which is basic and polar, with asparagine, which is neutral and polar, at codon 779 of the PDGFRA protein (p.Lys779Asn). This variant has not been reported in the literature in individuals affected with PDGFRA-related conditions. ClinVar contains an entry for this variant (Variation ID: 528590). 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 not expected to disrupt PDGFRA protein function. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 08, 2023

The p.K779N variant (also known as c.2337A>C), located in coding exon 16 of the PDGFRA gene, results from an A to C substitution at nucleotide position 2337. The lysine at codon 779 is replaced by asparagine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.42
CADD	Benign	17
DANN	Benign	0.97
DEOGEN2	Benign	0.20	.;T
Eigen	Benign	-0.59
Eigen_PC	Benign	-0.51
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Benign	0.72	T;T
M_CAP	Benign	0.049	D
MetaRNN	Benign	0.12	T;T
MetaSVM	Benign	-0.91	T
MutationAssessor	Benign	1.3	.;L
MutationTaster	Benign	1.0	N;D
PrimateAI	Uncertain	0.51	T
PROVEAN	Benign	-0.77	N;N
REVEL	Benign	0.17
Sift	Benign	0.24	T;T
Sift4G	Benign	0.34	T;T
Polyphen		0.41	.;B
Vest4		0.12
MutPred		0.47		.;Loss of ubiquitination at K779 (P = 0.0014);
MVP		0.42
MPC		0.55
ClinPred		0.19	T
GERP RS		-2.3
Varity_R		0.21
gMVP		0.49

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: rs1553905957; hg19: chr4-55151551;