X-15321606-T-A

Position:

• chrX-15321606-T-A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM2 PM5 PP3_Strong PP5_Moderate

The NM_002641.4(PIGA):​c.1355A>T​(p.Asp452Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D452N) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 23)
• Consequence: PIGA NM_002641.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.42

Genes affected

PIGA (HGNC:8957): (phosphatidylinositol glycan anchor biosynthesis class A) This gene encodes a protein required for synthesis of N-acetylglucosaminyl phosphatidylinositol (GlcNAc-PI), the first intermediate in the biosynthetic pathway of GPI anchor. The GPI anchor is a glycolipid found on many blood cells and which serves to anchor proteins to the cell surface. Paroxysmal nocturnal hemoglobinuria, an acquired hematologic disorder, has been shown to result from mutations in this gene. Alternate splice variants have been characterized. A related pseudogene is located on chromosome 12. [provided by RefSeq, Jun 2010]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrX-15321607-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 860851.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.94
• PP5: Variant X-15321606-T-A is Pathogenic according to our data. Variant chrX-15321606-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 973228.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PIGA	NM_002641.4	c.1355A>T	p.Asp452Val	missense_variant	6/6	ENST00000333590.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PIGA	ENST00000333590.6	c.1355A>T	p.Asp452Val	missense_variant	6/6	1	NM_002641.4	P1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 23

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Multiple congenital anomalies-hypotonia-seizures syndrome 2;C3806670:Paroxysmal nocturnal hemoglobinuria 1 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Institute for Genomic Medicine (IGM) Clinical Laboratory, Nationwide Children's Hospital

Apr 11, 2018

[ACMG/AMP: PS2, PM2, PP3] This alteration is de novo in origin as it was not detected in the submitted parental specimens (identity confirmed) [PS2], is absent from or rarely observed in large-scale population databases [PM2], is predicted to be damaging by multiple functional prediction tools [PP3]. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.91
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.77	D;D;T;.;.;.
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.97	.;D;D;D;D;D
M_CAP	Pathogenic	0.80	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D;D
MetaSVM	Uncertain	0.043	D
MutationAssessor	Pathogenic	3.6	H;H;.;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.52	T
PROVEAN	Pathogenic	-5.5	D;.;.;.;.;.
REVEL	Pathogenic	0.79
Sift	Pathogenic	0.0	D;.;.;.;.;.
Sift4G	Pathogenic	0.0010	D;D;.;D;D;.
Polyphen		1.0	D;D;.;.;D;.
Vest4		0.74
MutPred		0.75		Gain of sheet (P = 0.0085);Gain of sheet (P = 0.0085);.;.;.;.;
MVP		0.91
MPC		1.8
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.91
gMVP		0.98

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: rs1921817445; hg19: chrX-15339728;