X-133536153-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_004484.4(GPC3):c.1714G>T(p.Val572Leu) 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. 13/20 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. V572M) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 21)
• Consequence: GPC3 NM_004484.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.0500

Genes affected

GPC3 (HGNC:4451): (glypican 3) Cell surface heparan sulfate proteoglycans are composed of a membrane-associated protein core substituted with a variable number of heparan sulfate chains. Members of the glypican-related integral membrane proteoglycan family (GRIPS) contain a core protein anchored to the cytoplasmic membrane via a glycosyl phosphatidylinositol linkage. These proteins may play a role in the control of cell division and growth regulation. The protein encoded by this gene can bind to and inhibit the dipeptidyl peptidase activity of CD26, and it can induce apoptosis in certain cell types. Deletion mutations in this gene are associated with Simpson-Golabi-Behmel syndrome, also known as Simpson dysmorphia syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.27801108).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GPC3	NM_004484.4	c.1714G>T	p.Val572Leu	missense_variant	8/8	ENST00000370818.8
GPC3	NM_001164617.2	c.1783G>T	p.Val595Leu	missense_variant	9/9
GPC3	NM_001164618.2	c.1666G>T	p.Val556Leu	missense_variant	8/8
GPC3	NM_001164619.2	c.1552G>T	p.Val518Leu	missense_variant	7/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GPC3	ENST00000370818.8	c.1714G>T	p.Val572Leu	missense_variant	8/8	1	NM_004484.4	P1

Frequencies

GnomAD3 genomes Cov.: 21

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 21

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Wilms tumor 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 17, 2019

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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with GPC3-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces valine with leucine at codon 572 of the GPC3 protein (p.Val572Leu). The valine residue is weakly conserved and there is a small physicochemical difference between valine and leucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Benign	-0.27	T
BayesDel_noAF	Benign	-0.62
Cadd	Benign	2.1
Dann	Benign	0.94
DEOGEN2	Benign	0.28	T;.;.
FATHMM_MKL	Benign	0.085	N
LIST_S2	Benign	0.81	T;T;T
M_CAP	Pathogenic	0.30	D
MetaRNN	Benign	0.28	T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.4	L;.;.
MutationTaster	Benign	1.0	N;N;N
PrimateAI	Benign	0.40	T
PROVEAN	Benign	0.11	N;N;.
REVEL	Benign	0.056
Sift	Benign	0.051	T;D;.
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		0.012	B;.;.
Vest4		0.19
MutPred		0.63		Gain of helix (P = 0.0117);.;.;
MVP		0.38
MPC		0.18
ClinPred		0.57	D
GERP RS		4.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.12
gMVP		0.70

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: rs2069287188; hg19: chrX-132670181;