rs201344338

Positions:

• chrX-133753912-G-A
• chrX-133753912-G-C
• chrX-133753912-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_004484.4(GPC3):​c.602C>T​(p.Ala201Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: GPC3 NM_004484.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.50

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GPC3	NM_004484.4	c.602C>T	p.Ala201Val	missense_variant	3/8	ENST00000370818.8	NP_004475.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GPC3	ENST00000370818.8	c.602C>T	p.Ala201Val	missense_variant	3/8	1	NM_004484.4	ENSP00000359854	P1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 23

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

Labcorp Genetics (formerly Invitae), Labcorp

Feb 27, 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 sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. 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 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 alanine with valine at codon 201 of the GPC3 protein (p.Ala201Val). The alanine residue is highly conserved and there is a small physicochemical difference between alanine and valine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.25
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.42
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.48	T;.;.
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.89	D;D;D
M_CAP	Pathogenic	0.42	D
MetaRNN	Uncertain	0.55	D;D;D
MetaSVM	Benign	-0.69	T
MutationAssessor	Benign	1.9	L;L;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.53	T
PROVEAN	Uncertain	-2.6	D;D;.
REVEL	Benign	0.22
Sift	Benign	0.064	T;T;.
Sift4G	Uncertain	0.049	D;D;T
Polyphen		0.60	P;.;.
Vest4		0.21
MutPred		0.77		Gain of MoRF binding (P = 0.085);Gain of MoRF binding (P = 0.085);.;
MVP		0.40
MPC		0.54
ClinPred		0.95	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.66
gMVP		0.76

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

Publications

LitVar

Other links and lift over

dbSNP: rs201344338; hg19: chrX-132887939;