17-36537234-TAC-T

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_StrongPM2

The NM_001346754.2(PIGW):c.134_135delAC(p.Tyr45PhefsTer11) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000197 in 152,210 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

PIGW
NM_001346754.2 frameshift

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.562

Variant links:

Genes affected

PIGW (HGNC:23213): (phosphatidylinositol glycan anchor biosynthesis class W) The protein encoded by this gene is an inositol acyltransferase that acylates the inositol ring of phosphatidylinositol. This occurs in the endoplasmic reticulum and is a step in the biosynthesis of glycosylphosphatidylinositol (GPI), which anchors many cell surface proteins to the membrane. Defects in this gene are a cause of the age-dependent epileptic encephalopathy West syndrome as well as a syndrome exhibiting hyperphosphatasia and cognitive disability (HPMRS5). [provided by RefSeq, Jul 2017]

PIGW links:

MYO19 (HGNC:26234): (myosin XIX) Enables actin binding activity. Involved in regulation of cytokinesis and regulation of mitochondrial fission. Acts upstream of or within mitochondrion migration along actin filament. Located in cytosol and mitochondrial outer membrane. [provided by Alliance of Genome Resources, Apr 2022]

MYO19 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 4 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PIGW	NM_001346754.2 link	c.134_135delAC	p.Tyr45PhefsTer11	frameshift_variant	Exon 2 of 2	ENST00000614443.2	NP_001333683.1	Q7Z7B1
PIGW	NM_001346755.2 link	c.134_135delAC	p.Tyr45PhefsTer11	frameshift_variant	Exon 2 of 2		NP_001333684.1	Q7Z7B1
PIGW	NM_178517.5 link	c.134_135delAC	p.Tyr45PhefsTer11	frameshift_variant	Exon 2 of 2		NP_848612.2	Q7Z7B1
MYO19	XM_047436823.1 link	c.-295-3132_-295-3131delGT		intron_variant	Intron 2 of 29		XP_047292779.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PIGW	ENST00000614443.2 link	c.134_135delAC	p.Tyr45PhefsTer11	frameshift_variant	Exon 2 of 2	1	NM_001346754.2	ENSP00000482202.1		Q7Z7B1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152210

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD4 exome

Data not reliable, filtered out with message: AS_VQSR

AF:

0.00000137

AC:

AN:

1461876

Hom.:

AF XY:

0.00

AC XY:

AN XY:

727236

show subpopulations

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:

0.00000180

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152210

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74362

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Hyperphosphatasia with intellectual disability syndrome 5

Uncertain:1

Oct 15, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Tyr45Phefs*11) in the PIGW gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 460 amino acid(s) of the PIGW protein. This variant is present in population databases (no rsID available, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with PIGW-related conditions. ClinVar contains an entry for this variant (Variation ID: 1360698). 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over