rs587777543

chr16-575837-A-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1_Moderate PM2 PP3_Strong PP5_Moderate

The NM_004204.5(PIGQ):c.690-2A>G variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000709 in 1,409,580 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 7.1e-7 (0 hom.)
• Consequence: PIGQ NM_004204.5 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 8.32

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 Pathogenic. Variant got 10 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.075028636 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 16-575837-A-G is Pathogenic according to our data. Variant chr16-575837-A-G is described in ClinVar as [Pathogenic]. Clinvar id is 140458.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr16-575837-A-G is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PIGQ	NM_004204.5	c.690-2A>G		splice_acceptor_variant		ENST00000321878.10
PIGQ	NM_148920.4	c.690-2A>G		splice_acceptor_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PIGQ	ENST00000321878.10	c.690-2A>G		splice_acceptor_variant		1	NM_004204.5	P1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.00000571 AC: 1 AN: 175014 Hom.: 0 AF XY: 0.0000107 AC XY: 1 AN XY: 93188

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000364

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 7.09e-7 AC: 1 AN: 1409580 Hom.: 0 Cov.: 33 AF XY: 0.00000144 AC XY: 1 AN XY: 696644

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000262

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

Alfa AF: 0.0000936 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Developmental and epileptic encephalopathy, 77 Pathogenic:2

Pathogenic, no assertion criteria provided	literature only	OMIM	Jun 15, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Centre for Mendelian Genomics, University Medical Centre Ljubljana	Apr 02, 2020	This variant was classified as: Pathogenic. The following ACMG criteria were applied in classifying this variant: PVS1,PS3,PM2,PS4_SUPP. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	-0.050
Cadd	Uncertain	25
Dann	Benign	0.97
Eigen	Pathogenic	0.86
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D;D;D;D
GERP RS		4.9

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.39		Position offset: 4
DS_AL_spliceai		0.99		Position offset: 2

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

Publications

LitVar

Other links and lift over

dbSNP: rs587777543; hg19: chr16-625837;