4-530476-G-C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2PP3

The NM_001127178.3(PIGG):​c.2302G>C​(p.Gly768Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000397 in 1,613,646 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 (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000042 ( 0 hom. )

Consequence

PIGG
NM_001127178.3 missense

Scores

6
9
3

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 8.92

Publications

1 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.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.821

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001127178.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
PIGG
NM_001127178.3
MANE Select
c.2302G>Cp.Gly768Arg
missense
Exon 11 of 13NP_001120650.1
PIGG
NM_017733.5
c.2278G>Cp.Gly760Arg
missense
Exon 11 of 13NP_060203.3
PIGG
NM_001289051.2
c.2035G>Cp.Gly679Arg
missense
Exon 11 of 13NP_001275980.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
PIGG
ENST00000453061.7
TSL:1 MANE Select
c.2302G>Cp.Gly768Arg
missense
Exon 11 of 13ENSP00000415203.2
PIGG
ENST00000383028.8
TSL:1
c.1903G>Cp.Gly635Arg
missense
Exon 9 of 11ENSP00000372494.4
PIGG
ENST00000310340.9
TSL:2
c.2278G>Cp.Gly760Arg
missense
Exon 11 of 13ENSP00000311750.5

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
152074
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000517
AC:
13
AN:
251388
AF XY:
0.0000442
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000114
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000424
AC:
62
AN:
1461572
Hom.:
0
Cov.:
30
AF XY:
0.0000440
AC XY:
32
AN XY:
727116
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86246
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000504
AC:
56
AN:
1111724
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.490
Heterozygous variant carriers
0
3
7
10
14
17
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
152074
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74254
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41392
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10586
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.000113
Hom.:
0
Bravo
AF:
0.0000378
ExAC
AF:
0.0000494
AC:
6
EpiCase
AF:
0.000327
EpiControl
AF:
0.000237

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

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 glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 768 of the PIGG protein (p.Gly768Arg). This variant is present in population databases (rs35206248, gnomAD 0.01%). 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: 576871). 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 v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.92
BayesDel_addAF
Uncertain
0.081
D
BayesDel_noAF
Uncertain
0.090
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.12
T
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.77
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.96
D
M_CAP
Benign
0.030
D
MetaRNN
Pathogenic
0.82
D
MetaSVM
Benign
-1.1
T
MutationAssessor
Uncertain
2.8
M
PhyloP100
8.9
PrimateAI
Uncertain
0.74
T
PROVEAN
Uncertain
-4.0
D
REVEL
Uncertain
0.47
Sift
Uncertain
0.0080
D
Sift4G
Uncertain
0.0090
D
Polyphen
1.0
D
Vest4
0.98
MVP
0.46
MPC
0.76
ClinPred
0.89
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.60
gMVP
0.91
Mutation Taster
=32/68
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.070
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: rs35206248; hg19: chr4-524265; COSMIC: COSV108104763; COSMIC: COSV108104763; API