rs201186795

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_001127178.3(PIGG):​c.1862C>T​(p.Ala621Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000259 in 1,614,044 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A621A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000099 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00028 ( 0 hom. )

Consequence

PIGG
NM_001127178.3 missense

Scores

19

Clinical Significance

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

Conservation

PhyloP100: -0.597

Publications

6 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: Likely_benign. The variant received -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.06062296).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PIGGNM_001127178.3 linkc.1862C>T p.Ala621Val 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.1862C>T p.Ala621Val missense_variant Exon 9 of 13 1 NM_001127178.3 ENSP00000415203.2 Q5H8A4-1

Frequencies

GnomAD3 genomes
AF:
0.0000986
AC:
15
AN:
152206
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.000162
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000195
AC:
49
AN:
251144
AF XY:
0.000236
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000867
Gnomad ASJ exome
AF:
0.0000993
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.000388
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000276
AC:
403
AN:
1461838
Hom.:
0
Cov.:
33
AF XY:
0.000264
AC XY:
192
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.0000894
AC:
4
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.000115
AC:
3
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53382
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000339
AC:
377
AN:
1111996
Other (OTH)
AF:
0.000265
AC:
16
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.468
Heterozygous variant carriers
0
25
50
75
100
125
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<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:
0.0000986
AC:
15
AN:
152206
Hom.:
0
Cov.:
33
AF XY:
0.0000807
AC XY:
6
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.0000482
AC:
2
AN:
41454
American (AMR)
AF:
0.000131
AC:
2
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000162
AC:
11
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.000221
Hom.:
1
Bravo
AF:
0.000128
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000255
AC:
31
EpiCase
AF:
0.000436
EpiControl
AF:
0.000356

ClinVar

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

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Jan 19, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1862C>T (p.A621V) alteration is located in exon 9 (coding exon 9) of the PIGG gene. This alteration results from a C to T substitution at nucleotide position 1862, causing the alanine (A) at amino acid position 621 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Intellectual disability, autosomal recessive 53 Uncertain:1
Dec 22, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 621 of the PIGG protein (p.Ala621Val). This variant is present in population databases (rs201186795, gnomAD 0.04%). 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: 476326). 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 not expected to disrupt PIGG protein function with a negative predictive value of 80%. 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
Benign
0.077
BayesDel_addAF
Benign
-0.56
T
BayesDel_noAF
Benign
-0.72
CADD
Benign
4.8
DANN
Benign
0.66
DEOGEN2
Benign
0.011
.;T;T;.
Eigen
Benign
-1.1
Eigen_PC
Benign
-1.2
FATHMM_MKL
Benign
0.15
N
LIST_S2
Benign
0.58
T;T;T;T
M_CAP
Benign
0.0021
T
MetaRNN
Benign
0.061
T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
1.4
.;L;.;.
PhyloP100
-0.60
PrimateAI
Benign
0.27
T
PROVEAN
Benign
-0.77
N;N;N;N
REVEL
Benign
0.092
Sift
Benign
0.18
T;T;T;T
Sift4G
Benign
0.15
T;T;T;T
Polyphen
0.069
B;B;.;B
Vest4
0.14
MVP
0.42
MPC
0.17
ClinPred
0.023
T
GERP RS
-0.096
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.026
gMVP
0.24
Mutation Taster
=95/5
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: rs201186795; hg19: chr4-517495; COSMIC: COSV56321190; COSMIC: COSV56321190; API