rs200850789

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM5PP3

The NM_001127178.3(PIGG):​c.2006G>A​(p.Arg669His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000539 in 1,594,938 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R669C) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.00013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000046 ( 0 hom. )

Consequence

PIGG
NM_001127178.3 missense

Scores

8
8
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 9.15

Publications

4 publications found
Variant links:
Genes affected
PIGG (HGNC:25985): (phosphatidylinositol glycan anchor biosynthesis class G (EMM blood group)) This gene encodes an enzyme involved in glycosylphosphatidylinositol-anchor biosynthesis. The encoded protein, which is localized to the endoplasmic reticulum, is involved in transferring ethanoloamine phosphate to mannose 2 of glycosylphosphatidylinositol species H7 to form species H8. Allelic variants of this gene have been associated with intellectual disability, hypotonia, and early-onset seizures. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2016]
PIGG Gene-Disease associations (from GenCC):
  • intellectual disability, autosomal recessive 53
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr4-523849-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 225638.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.779

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PIGGNM_001127178.3 linkc.2006G>A p.Arg669His missense_variant Exon 9 of 13 ENST00000453061.7 NP_001120650.1 Q5H8A4-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PIGGENST00000453061.7 linkc.2006G>A p.Arg669His missense_variant Exon 9 of 13 1 NM_001127178.3 ENSP00000415203.2 Q5H8A4-1

Frequencies

GnomAD3 genomes
AF:
0.000131
AC:
20
AN:
152226
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000338
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000530
AC:
11
AN:
207742
AF XY:
0.0000530
show subpopulations
Gnomad AFR exome
AF:
0.000247
Gnomad AMR exome
AF:
0.0000333
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000659
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000668
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000458
AC:
66
AN:
1442594
Hom.:
0
Cov.:
32
AF XY:
0.0000447
AC XY:
32
AN XY:
716186
show subpopulations
African (AFR)
AF:
0.000151
AC:
5
AN:
33010
American (AMR)
AF:
0.0000242
AC:
1
AN:
41400
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25790
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38610
South Asian (SAS)
AF:
0.0000238
AC:
2
AN:
84110
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51152
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5740
European-Non Finnish (NFE)
AF:
0.0000526
AC:
58
AN:
1103100
Other (OTH)
AF:
0.00
AC:
0
AN:
59682
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
4
7
11
14
18
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000131
AC:
20
AN:
152344
Hom.:
0
Cov.:
33
AF XY:
0.000121
AC XY:
9
AN XY:
74492
show subpopulations
African (AFR)
AF:
0.000337
AC:
14
AN:
41588
American (AMR)
AF:
0.0000654
AC:
1
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.467
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000102
Hom.:
0
Bravo
AF:
0.000136
ESP6500AA
AF:
0.000231
AC:
1
ESP6500EA
AF:
0.000117
AC:
1
ExAC
AF:
0.0000581
AC:
7

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:1
May 01, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Intellectual disability, autosomal recessive 53 Uncertain:1
Oct 17, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 669 of the PIGG protein (p.Arg669His). This variant is present in population databases (rs200850789, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with PIGG-related conditions. ClinVar contains an entry for this variant (Variation ID: 542887). 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 PIGG protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.51
BayesDel_addAF
Uncertain
0.055
T
BayesDel_noAF
Uncertain
0.11
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.25
.;T;T;.
Eigen
Pathogenic
0.97
Eigen_PC
Pathogenic
0.92
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Pathogenic
0.98
D;D;D;D
M_CAP
Benign
0.023
T
MetaRNN
Pathogenic
0.78
D;D;D;D
MetaSVM
Uncertain
0.084
D
MutationAssessor
Pathogenic
3.0
.;M;.;.
PhyloP100
9.2
PrimateAI
Uncertain
0.67
T
PROVEAN
Pathogenic
-4.4
D;D;D;D
REVEL
Pathogenic
0.67
Sift
Uncertain
0.0010
D;D;D;D
Sift4G
Uncertain
0.0040
D;D;D;D
Polyphen
1.0
D;D;.;D
Vest4
0.90
MVP
0.94
MPC
0.77
ClinPred
0.86
D
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.53
gMVP
0.82
Mutation Taster
=78/22
polymorphism

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

Other links and lift over

dbSNP: rs200850789; hg19: chr4-517639; COSMIC: COSV99574048; COSMIC: COSV99574048; API