4-521778-C-T

Variant names:

Variant summary

Our verdict is Benign. Variant got -14 ACMG points: 2P and 16B. PM2BP4_StrongBP6_Very_StrongBS1

The NM_001345990.2(PIGG):c.-83C>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000241 in 1,614,198 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0011 ( 1 hom., cov: 33)

Exomes 𝑓: 0.00015 ( 0 hom. )

Consequence

PIGG
NM_001345990.2 5_prime_UTR_premature_start_codon_gain

Scores

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:6

Conservation

PhyloP100: 1.81

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -14 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.012878656).

BP6

Variant 4-521778-C-T is Benign according to our data. Variant chr4-521778-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 476317.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr4-521778-C-T is described in Lovd as [Likely_benign].

BS1

Variant frequency is greater than expected in population afr. gnomad4_exome allele frequency = 0.000151 (221/1461890) while in subpopulation AFR AF= 0.0043 (144/33478). AF 95% confidence interval is 0.00373. There are 0 homozygotes in gnomad4_exome. There are 108 alleles in male gnomad4_exome subpopulation. Median coverage is 32. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PIGG	NM_001127178.3 link	c.1451C>T	p.Ser484Leu	missense_variant	Exon 8 of 13	ENST00000453061.7	NP_001120650.1	Q5H8A4-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PIGG	ENST00000453061.7 link	c.1451C>T	p.Ser484Leu	missense_variant	Exon 8 of 13	1	NM_001127178.3	ENSP00000415203.2		Q5H8A4-1

Frequencies

GnomAD3 genomes

AF:

0.00111

AC:

169

AN:

152190

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00343

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00137

Gnomad ASJ

AF:

0.000288

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00949

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000310

AC:

AN:

251482

Hom.:

AF XY:

0.000169

AC XY:

AN XY:

135918

show subpopulations

Gnomad AFR exome

AF:

0.00375

Gnomad AMR exome

AF:

0.000260

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000980

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.000489

GnomAD4 exome

AF:

0.000151

AC:

221

AN:

1461890

Hom.:

Cov.:

AF XY:

0.000149

AC XY:

108

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.00430

Gnomad4 AMR exome

AF:

0.000470

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000504

Gnomad4 SAS exome

AF:

0.0000464

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000126

Gnomad4 OTH exome

AF:

0.000546

GnomAD4 genome

AF:

0.00110

AC:

168

AN:

152308

Hom.:

Cov.:

AF XY:

0.000940

AC XY:

AN XY:

74470

show subpopulations

Gnomad4 AFR

AF:

0.00342

Gnomad4 AMR

AF:

0.00137

Gnomad4 ASJ

AF:

0.000288

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000273

Hom.:

Bravo

AF:

0.00154

ESP6500AA

AF:

0.00363

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.000379

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Likely benign

Submissions summary: Benign:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Benign:3

May 17, 2021

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

not specified

Benign:1

Apr 17, 2024

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: PIGG c.1451C>T (p.Ser484Leu) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00024 in 1614198 control chromosomes, predominantly at a frequency of 0.0038 within the African or African-American subpopulation in the gnomAD database, including 1 homozygotes. The observed variant frequency within African or African-American control individuals in the gnomAD database is above of the estimated maximal expected allele frequency for a pathogenic variant in PIGG causing Intellectual Disability, Autosomal Recessive 53 phenotype, strongly suggesting that the variant is a benign polymorphism found primarily in populations of African or African-American origin. To our knowledge, no occurrence of c.1451C>T in individuals affected with Intellectual Disability, Autosomal Recessive 53 and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 476317). Based on the evidence outlined above, the variant was classified as likely benign. -

Inborn genetic diseases

Benign:1

Jan 23, 2024

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Intellectual disability, autosomal recessive 53

Benign:1

Feb 03, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.068

BayesDel_addAF

Benign

-0.51

BayesDel_noAF

Benign

-0.50

CADD

Benign

DANN

Benign

0.53

DEOGEN2

Benign

0.024

.;T;T;.;.

Eigen

Benign

-0.53

Eigen_PC

Benign

-0.61

FATHMM_MKL

Benign

0.52

LIST_S2

Benign

0.84

T;T;T;T;T

M_CAP

Benign

0.021

MetaRNN

Benign

0.013

T;T;T;T;T

MetaSVM

Benign

-0.93

MutationAssessor

Uncertain

2.4

.;M;.;.;.

PrimateAI

Benign

0.41

PROVEAN

Uncertain

-2.6

D;D;D;N;D

REVEL

Benign

0.17

Sift

Benign

0.21

T;T;T;T;T

Sift4G

Benign

0.65

T;T;T;T;T

Polyphen

0.82

P;P;.;D;B

Vest4

0.11

MVP

0.58

MPC

0.15

ClinPred

0.040

GERP RS

-0.21

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.061

gMVP

0.61

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over