rs139073416

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PM5PP3_ModeratePP5_Very_Strong

The NM_017837.4(PIGV):โ€‹c.1022C>Aโ€‹(p.Ala341Glu) variant causes a missense change. The variant allele was found at a frequency of 0.0000905 in 1,614,076 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 Likely pathogenic (โ˜…โ˜…). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A341V) has been classified as Pathogenic.

Frequency

Genomes: ๐‘“ 0.00014 ( 0 hom., cov: 32)
Exomes ๐‘“: 0.000086 ( 0 hom. )

Consequence

PIGV
NM_017837.4 missense

Scores

7
9
3

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:14

Conservation

PhyloP100: 5.69
Variant links:
Genes affected
PIGV (HGNC:26031): (phosphatidylinositol glycan anchor biosynthesis class V) This gene encodes a mannosyltransferase enzyme involved in the biosynthesis of glycosylphosphatidylinositol (GPI). GPI is a complex glycolipid that functions as a membrane anchor for many proteins and plays a role in multiple cellular processes including protein sorting and signal transduction. The encoded protein is localized to the endoplasmic reticulum and transfers the second mannose to the GPI backbone. Mutations in this gene are associated with hyperphosphatasia cognitive disability syndrome. Alternatively spliced transcript variants have been observed for this gene. [provided by RefSeq, Feb 2011]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM1
In a transmembrane_region Helical (size 20) in uniprot entity PIGV_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) in NM_017837.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-26795056-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 1287.Status of the report is no_assertion_criteria_provided, 0 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.862
PP5
Variant 1-26795056-C-A is Pathogenic according to our data. Variant chr1-26795056-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1284.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-26795056-C-A is described in Lovd as [Likely_pathogenic]. Variant chr1-26795056-C-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
PIGVNM_017837.4 linkuse as main transcriptc.1022C>A p.Ala341Glu missense_variant 3/4 ENST00000674202.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
PIGVENST00000674202.1 linkuse as main transcriptc.1022C>A p.Ala341Glu missense_variant 3/4 NM_017837.4 P1

Frequencies

GnomAD3 genomes
AF:
0.000138
AC:
21
AN:
152192
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000265
Gnomad OTH
AF:
0.000479
GnomAD3 exomes
AF:
0.000115
AC:
29
AN:
251478
Hom.:
0
AF XY:
0.0000956
AC XY:
13
AN XY:
135914
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
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:
0.000246
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000855
AC:
125
AN:
1461884
Hom.:
0
Cov.:
34
AF XY:
0.0000894
AC XY:
65
AN XY:
727242
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.0000765
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.000111
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.000138
AC:
21
AN:
152192
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74348
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.000288
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000265
Gnomad4 OTH
AF:
0.000479
Alfa
AF:
0.000148
Hom.:
0
Bravo
AF:
0.000159
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.000148
AC:
18
EpiCase
AF:
0.000164
EpiControl
AF:
0.00

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:14
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hyperphosphatasia with intellectual disability syndrome 1 Pathogenic:8
Pathogenic, criteria provided, single submitterclinical testingInstitute of Human Genetics, University of Leipzig Medical CenterAug 11, 2017This variant was identified comp-het. with Chr1: 27121132; NM_017837.3: c.607C>T; p.(Arg203Cys) -
Pathogenic, no assertion criteria providedliterature onlyOMIMMar 01, 2012- -
Pathogenic, criteria provided, single submitterclinical testingGreenwood Genetic Center Diagnostic Laboratories, Greenwood Genetic CenterSep 15, 2023PS3, PM3_strong, PM2, PM5_supporting -
Pathogenic, criteria provided, single submitterclinical testingMayo Clinic Laboratories, Mayo ClinicJan 27, 2017- -
Pathogenic, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 11, 2019Across a selection of the literature, the PIGV c.1022C>A (p.Ala341Glu) missense variant was observed in a total of 17 individuals with hyperphosphatasia with mental retardation syndrome, including in nine in a homozygous state (three of whom were related) and in eight in a compound heterozygous state (two of whom were related). The p.Ala341Glu variant was absent from 350 controls and 4,000 exomes (Krawitz et al. 2010; Horn et al. 2011; Thompson et al. 2012; Horn et al. 2014). The variant is reported at a frequency of 0.000349 in the European American population of the Exome Sequencing Project. Functional studies by Krawitz et al. (2010) showed that PIGV-deficient CHO cells transfected with wild type PIGV were able to restore surface expression of marker proteins, but that cells carrying the p.Ala341Glu variant were unable to restore expression. Murakami et al. (2012) produced similar results, and also demonstrated that expression of the p.Ala341Glu variant protein was drastically reduced as compared to wild type. The highest allele frequency reported in the Exome Sequencing Project is 0.00035 in the European American population. Based on the collective evidence, the p.Ala341Glu variant is classified as pathogenic for hyperphosphatasia with intellectual disability syndrome. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -
Pathogenic, criteria provided, single submitterclinical testingInstitute for Genomic Statistics and Bioinformatics, University Hospital Bonn-- -
Pathogenic, criteria provided, single submitterliterature onlyDepartment of Clinical Genetics, Medical University of LodzJul 27, 2023- -
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsDec 30, 2021- -
not provided Pathogenic:3
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpDec 13, 2023This sequence change replaces alanine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 341 of the PIGV protein (p.Ala341Glu). This variant is present in population databases (rs139073416, gnomAD 0.02%). This missense change has been observed in individuals with hyperphosphatasia mental retardation syndrome (PMID: 20802478, 28688840). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 1284). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt PIGV protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects PIGV function (PMID: 20802478). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingGeneDxJan 13, 2022Published functional studies demonstrate a damaging effect (Krawitz et al., 2010; Murakami et al., 2012); This variant is associated with the following publications: (PMID: 20802478, 22228761, 24129430, 22315194, 21739589, 28688840, 31980526, 33402532, 31589614, 33144682) -
Pathogenic, criteria provided, single submitterclinical testingInstitute of Medical Genetics and Applied Genomics, University Hospital TรผbingenOct 23, 2020- -
Inborn genetic diseases Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingAmbry GeneticsAug 08, 2013- -
PIGV-related disorder Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesAug 04, 2024The PIGV c.1022C>A variant is predicted to result in the amino acid substitution p.Ala341Glu. This variant in the homozygous and compound heterozygous conditions were reported to be pathogenic for autosomal recessive hyperphosphatasia with intellectual disability syndrome, and hyperphosphatasia with seizures and neurologic deficit (Krawitz et al. 2010. PubMed ID: 20802478; Evers et al. 2017. PubMed ID: 28688840; Horn et al. 2011. PubMed ID: 21739589; Thompson et al. 2012. PubMed ID: 22315194). A different variant affecting the same amino acid residue (p.Ala341Val) was reported to be pathogenic (Thompson et al. 2012. PubMed ID: 22315194). This variant is reported in 0.023% of alleles in individuals of European (Non-Finnish) descent in gnomAD. This variant is interpreted as pathogenic. -
Hyperphosphatasia-intellectual disability syndrome Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineJan 27, 2017The p.Ala341Glu variant in PIGV has been identified in at least 10 individuals w ith hyperphosphatasia-intellectual disability syndrome (HPMR; Krawitz 2010, Horn 2011, Murakami 2012, Horn 2014), all of whom were either homozygous or compound heterozygous. This variant segregated with disease in at least 2 affected famil y members. It was also identified in 0.02% (30/126708) of European chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; db SNP rs139073416). Although this variant has been seen in the general population, its frequency is low enough to be consistent with a recessive carrier frequency . Furthermore, in vitro functional studies provide some evidence that the p.Ala3 41Glu variant may impact protein function (Murakami 2012). In summary, although additional studies are required to fully establish its clinical significance, th e p.Ala341Glu variant is likely pathogenic for hyperphosphatasia-intellectual di sability syndrome inherited in an autosomal recessive manner. ACMG/AMP Criteria applied: PM3_Strong, PM2_Supporting, PP1, PS3_Supporting (Richards 2015). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.84
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Pathogenic
0.38
CADD
Uncertain
25
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.64
D;D
Eigen
Uncertain
0.65
Eigen_PC
Uncertain
0.58
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Benign
0.77
.;T
M_CAP
Uncertain
0.14
D
MetaRNN
Pathogenic
0.86
D;D
MetaSVM
Uncertain
0.70
D
MutationAssessor
Pathogenic
3.4
M;M
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Uncertain
0.63
T
PROVEAN
Benign
-2.2
N;N
REVEL
Pathogenic
0.83
Sift
Uncertain
0.0030
D;D
Sift4G
Uncertain
0.0040
D;D
Polyphen
0.96
D;D
Vest4
0.85
MVP
0.96
MPC
0.66
ClinPred
0.46
T
GERP RS
4.1
Varity_R
0.64
gMVP
0.89

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs139073416; hg19: chr1-27121547; API