rs201835155

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP3_StrongPP5

The NM_176787.5(PIGN):​c.1694G>T​(p.Arg565Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000131 in 1,607,982 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000086 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000055 ( 0 hom. )

Consequence

PIGN
NM_176787.5 missense

Scores

11
7
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:4

Conservation

PhyloP100: 6.18
Variant links:
Genes affected
PIGN (HGNC:8967): (phosphatidylinositol glycan anchor biosynthesis class N) This gene encodes a protein that is involved 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 protein is expressed in the endoplasmic reticulum and transfers phosphoethanolamine (EtNP) to the first mannose of the GPI anchor. Two alternatively spliced variants, which encode an identical isoform, have been reported. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

PM1
In a topological_domain Lumenal (size 0) in uniprot entity PIGN_HUMAN
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.961
PP5
Variant 18-62106862-C-A is Pathogenic according to our data. Variant chr18-62106862-C-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 391067.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=4, Pathogenic=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PIGNNM_176787.5 linkc.1694G>T p.Arg565Leu missense_variant Exon 19 of 31 ENST00000640252.2 NP_789744.1 O95427A0A024R2C3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PIGNENST00000640252.2 linkc.1694G>T p.Arg565Leu missense_variant Exon 19 of 31 1 NM_176787.5 ENSP00000492233.1 O95427
PIGNENST00000400334.7 linkc.1694G>T p.Arg565Leu missense_variant Exon 18 of 30 1 ENSP00000383188.2 O95427
PIGNENST00000638424.1 linkn.1694G>T non_coding_transcript_exon_variant Exon 17 of 29 5 ENSP00000491963.1 A0A1W2PQZ1

Frequencies

GnomAD3 genomes
AF:
0.0000855
AC:
13
AN:
151966
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000852
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000125
AC:
3
AN:
239518
Hom.:
0
AF XY:
0.00000772
AC XY:
1
AN XY:
129606
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000595
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:
0.00000926
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000549
AC:
8
AN:
1456016
Hom.:
0
Cov.:
31
AF XY:
0.00000553
AC XY:
4
AN XY:
723616
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000159
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:
0.0000166
GnomAD4 genome
AF:
0.0000855
AC:
13
AN:
151966
Hom.:
0
Cov.:
32
AF XY:
0.000108
AC XY:
8
AN XY:
74198
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.000852
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.00000501
Hom.:
0
Bravo
AF:
0.000189
ExAC
AF:
0.00000829
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:4Uncertain:4
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Multiple congenital anomalies-hypotonia-seizures syndrome 1 Pathogenic:2Uncertain:2
Jun 20, 2019
Centogene AG - the Rare Disease Company
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jul 19, 2018
Baylor Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

Mar 28, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 565 of the PIGN protein (p.Arg565Leu). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individual(s) with clinical features of PIGN-related conditions (PMID: 32220244, 35322241; internal data). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 391067). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt PIGN protein function with a positive predictive value of 80%. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1Uncertain:1
May 02, 2024
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Reported in a patient with features consistent with a PIGN-related disorder who had a second PIGN variant in trans (PMID: 32220244); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 35322241, 38256219, Xiuwei_2021, 38456468, 32220244) -

Mar 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

PIGN: PM2, PM3 -

Inborn genetic diseases Pathogenic:1
Jan 24, 2024
Ambry Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.R565L variant (also known as c.1694G>T), located in coding exon 16 of the PIGN gene, results from a G to T substitution at nucleotide position 1694. The arginine at codon 565 is replaced by leucine, an amino acid with dissimilar properties. This variant has been confirmed in trans with a PIGN likely pathogenic/pathogenic variant in two individuals with clinical features of PIGN-related glycosylphosphatidylinositol deficiency (Ambry internal data; Brea-Fernández AJ et al. Eur J Hum Genet, 2022 Aug;30:938-945). Another alteration at the same codon, c.1694G>A (p.R565H), has been detected in an individual with clinical features consistent with PIGN-related glycosylphosphatidylinositol deficiency (Jiao X et al. Orphanet J Rare Dis, 2020 Mar;15:78). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

not specified Uncertain:1
May 04, 2022
Mendelics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.94
BayesDel_addAF
Pathogenic
0.22
D
BayesDel_noAF
Pathogenic
0.28
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.57
D;.;D;D;D;.;.;.;.;.;D;.;.;D;.;D;.;.
Eigen
Pathogenic
0.97
Eigen_PC
Pathogenic
0.92
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.98
.;.;.;.;.;.;D;.;D;D;.;D;D;.;D;D;D;D
M_CAP
Uncertain
0.16
D
MetaRNN
Pathogenic
0.96
D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.19
D
MutationAssessor
Pathogenic
3.4
M;.;M;M;M;.;.;.;.;.;M;.;.;M;.;M;.;.
PrimateAI
Uncertain
0.55
T
PROVEAN
Pathogenic
-6.5
.;.;.;D;.;.;.;.;.;.;D;.;.;.;.;.;.;.
REVEL
Uncertain
0.62
Sift
Uncertain
0.0030
.;.;.;D;.;.;.;.;.;.;D;.;.;.;.;.;.;.
Sift4G
Pathogenic
0.0
.;.;.;D;.;.;.;.;.;.;D;.;.;.;.;.;.;.
Polyphen
1.0
D;.;D;D;D;.;.;.;.;.;D;.;.;D;.;D;.;.
Vest4
0.94, 0.95
MutPred
0.88
Loss of catalytic residue at R565 (P = 0.0571);.;Loss of catalytic residue at R565 (P = 0.0571);Loss of catalytic residue at R565 (P = 0.0571);Loss of catalytic residue at R565 (P = 0.0571);.;.;Loss of catalytic residue at R565 (P = 0.0571);.;.;Loss of catalytic residue at R565 (P = 0.0571);Loss of catalytic residue at R565 (P = 0.0571);.;Loss of catalytic residue at R565 (P = 0.0571);.;Loss of catalytic residue at R565 (P = 0.0571);Loss of catalytic residue at R565 (P = 0.0571);Loss of catalytic residue at R565 (P = 0.0571);
MVP
0.93
MPC
0.21
ClinPred
0.99
D
GERP RS
6.1
Varity_R
0.79
gMVP
0.94

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
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.

Other links and lift over

dbSNP: rs201835155; hg19: chr18-59774095; API