rs587777400

Variant names:

• chrX-15331653-G-A
• rs587777400
• NM_002641.4:c.278C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_002641.4(PIGA):​c.278C>T​(p.Pro93Leu) 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. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 24)
• Consequence: PIGA NM_002641.4 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.48
• Publications: 8 publications found

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]

PIGA Gene-Disease associations (from GenCC):

• multiple congenital anomalies-hypotonia-seizures syndrome 2

  Inheritance: XL Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: G2P, Illumina, Labcorp Genetics (formerly Invitae), Orphanet
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• malignant migrating partial seizures of infancy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• ferro-cerebro-cutaneous syndrome

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• paroxysmal nocturnal hemoglobinuria

  Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 10 uncertain in NM_002641.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.953
• PP5: Variant X-15331653-G-A is Pathogenic according to our data. Variant chrX-15331653-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 132819.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PIGA	NM_002641.4	c.278C>T	p.Pro93Leu	missense_variant	Exon 2 of 6	ENST00000333590.6	NP_002632.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PIGA	ENST00000333590.6	c.278C>T	p.Pro93Leu	missense_variant	Exon 2 of 6	1	NM_002641.4	ENSP00000369820.3

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 24

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Multiple congenital anomalies-hypotonia-seizures syndrome 2 Pathogenic:1

Jan 01, 2014

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.87	D;D;.;.
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	.;D;D;D
M_CAP	Pathogenic	0.65	D
MetaRNN	Pathogenic	0.95	D;D;D;D
MetaSVM	Uncertain	0.51	D
MutationAssessor	Pathogenic	3.1	M;M;M;.
PhyloP100		9.5
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-9.7	D;.;.;.
REVEL	Pathogenic	0.85
Sift	Pathogenic	0.0	D;.;.;.
Sift4G	Pathogenic	0.0	D;D;D;.
Polyphen		1.0	D;D;D;.
Vest4		0.82
MutPred		0.81		Loss of sheet (P = 0.0181);Loss of sheet (P = 0.0181);Loss of sheet (P = 0.0181);Loss of sheet (P = 0.0181);
MVP		0.92
MPC		1.5
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.99
gMVP		0.99
Mutation Taster		=7/93	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs587777400; hg19: chrX-15349775;