chr21-37065665-T-A

Position:

chr21-37065665-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_153682.3(PIGP):c.322A>T(p.Ile108Phe) variant causes a missense change. The variant allele was found at a frequency of 0.0000031 in 1,613,292 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: 32)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

PIGP
NM_153682.3 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 4.53

Variant links:

Genes affected

PIGP (HGNC:3046): (phosphatidylinositol glycan anchor biosynthesis class P) This gene encodes an enzyme involved in the first step of glycosylphosphatidylinositol (GPI)-anchor biosynthesis. The GPI-anchor is a glycolipid found on many blood cells that serves to anchor proteins to the cell surface. The encoded protein is a component of the GPI-N-acetylglucosaminyltransferase complex that catalyzes the transfer of N-acetylglucosamine (GlcNAc) from UDP-GlcNAc to phosphatidylinositol (PI). This gene is located in the Down Syndrome critical region on chromosome 21 and is a candidate for the pathogenesis of Down syndrome. This gene has multiple pseudogenes and is a member of the phosphatidylinositol glycan anchor biosynthesis gene family. Alternatively spliced transcript variants encoding different isoforms have been described. [provided by RefSeq, Feb 2016]

PIGP links:

PIGP (HGNC:):

PIGP links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.765

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PIGP	NM_153682.3 linkuse as main transcript	c.322A>T	p.Ile108Phe	missense_variant	5/5	ENST00000360525.9	NP_710149.1	P57054-2
PIGP	NM_153681.2 linkuse as main transcript	c.394A>T	p.Ile132Phe	missense_variant	4/4		NP_710148.1	P57054-1
PIGP	NM_001320480.2 linkuse as main transcript	c.322A>T	p.Ile108Phe	missense_variant	5/5		NP_001307409.1	P57054-2
PIGP	NM_016430.4 linkuse as main transcript	c.244A>T	p.Ile82Phe	missense_variant	6/6		NP_057514.2	P57054-3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PIGP	ENST00000360525.9 linkuse as main transcript	c.322A>T	p.Ile108Phe	missense_variant	5/5	1	NM_153682.3	ENSP00000353719.3		P57054-2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152228

Hom.:

Cov.:

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

GnomAD3 exomes

AF:

0.00000402

AC:

AN:

248724

Hom.:

AF XY:

0.00000743

AC XY:

AN XY:

134628

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000898

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461064

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

726844

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000270

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152228

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74370

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

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

Bravo

AF:

0.0000113

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

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 06, 2023

The c.394A>T (p.I132F) alteration is located in exon 4 (coding exon 4) of the PIGP gene. This alteration results from a A to T substitution at nucleotide position 394, causing the isoleucine (I) at amino acid position 132 to be replaced by a phenylalanine (F). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 14, 2022

This sequence change replaces isoleucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 132 of the PIGP protein (p.Ile132Phe). This variant is present in population databases (rs200401315, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with PIGP-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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

0.30

BayesDel_addAF

Uncertain

0.086

BayesDel_noAF

Benign

-0.11

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Benign

0.14

.;T;.;.;.

Eigen

Pathogenic

0.78

Eigen_PC

Pathogenic

0.72

FATHMM_MKL

Uncertain

0.96

LIST_S2

Benign

0.83

.;T;.;T;T

M_CAP

Benign

0.034

MetaRNN

Pathogenic

0.77

D;D;D;D;D

MetaSVM

Benign

-0.47

MutationAssessor

Pathogenic

3.4

.;M;.;.;.

PrimateAI

Benign

0.44

PROVEAN

Uncertain

-3.6

D;D;D;D;D

REVEL

Uncertain

0.34

Sift

Uncertain

0.0020

D;D;D;D;D

Sift4G

Uncertain

0.0040

D;D;D;D;D

Polyphen

0.99

.;D;.;.;.

Vest4

0.50

MutPred

0.81

.;Gain of loop (P = 0.2045);.;.;.;

MVP

0.63

MPC

0.048

ClinPred

0.98

GERP RS

4.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.60

gMVP

0.87

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.030

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