16-574114-AC-GT

Variant summary

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

The NM_004204.5(PIGQ):c.40_41inv(p.Thr14Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. 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. T14A) has been classified as Benign.

• Frequency: Genomes: not found (cov: 34)
• Consequence: PIGQ NM_004204.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.63

Genes affected

PIGQ (HGNC:14135): (phosphatidylinositol glycan anchor biosynthesis class Q) This gene is involved in the first step in glycosylphosphatidylinositol (GPI)-anchor biosynthesis. The GPI-anchor is a glycolipid found on many blood cells and serves to anchor proteins to the cell surface. This gene encodes a N-acetylglucosaminyl transferase component that is part of the complex that catalyzes transfer of N-acetylglucosamine (GlcNAc) from UDP-GlcNAc to phosphatidylinositol (PI). Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2012]

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	UniProt
PIGQ	NM_004204.5	c.40_41inv	p.Thr14Val	missense_variant	2/11	ENST00000321878.10
PIGQ	NM_148920.4	c.40_41inv	p.Thr14Val	missense_variant	2/10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PIGQ	ENST00000321878.10	c.40_41inv	p.Thr14Val	missense_variant	2/11	1	NM_004204.5	P1

Frequencies

GnomAD3 genomes Cov.: 34

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Epilepsy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Mar 11, 2022

This sequence change replaces threonine, which is neutral and polar, with valine, which is neutral and non-polar, at codon 14 of the PIGQ protein (p.Thr14Val). This variant is present in population databases (no rsID available, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with PIGQ-related conditions. 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: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available"). 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

Splicing

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr16-624114;