20-45416226-G-A

Position:

chr20-45416226-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_015937.6(PIGT):c.70G>A(p.Glu24Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000157 in 1,596,666 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00011 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

PIGT
NM_015937.6 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 1.50

Variant links:

Genes affected

PIGT (HGNC:14938): (phosphatidylinositol glycan anchor biosynthesis class T) This gene encodes a protein that is involved in glycosylphosphatidylinositol (GPI)-anchor biosynthesis. The GPI-anchor is a glycolipid found on many blood cells and serves to anchor proteins to the cell surface. This protein is an essential component of the multisubunit enzyme, GPI transamidase. GPI transamidase mediates GPI anchoring in the endoplasmic reticulum, by catalyzing the transfer of fully assembled GPI units to proteins. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, May 2012]

PIGT links:

LOC107985405 (HGNC:):

LOC107985405 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.09583068).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PIGT	NM_015937.6 linkuse as main transcript	c.70G>A	p.Glu24Lys	missense_variant	1/12	ENST00000279036.12	NP_057021.2
LOC107985405	XR_001754640.2 linkuse as main transcript	n.762C>T		non_coding_transcript_exon_variant	2/2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PIGT	ENST00000279036.12 linkuse as main transcript	c.70G>A	p.Glu24Lys	missense_variant	1/12	1	NM_015937.6	ENSP00000279036	P1	Q969N2-1

Frequencies

GnomAD3 genomes

AF:

0.000105

AC:

AN:

152264

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000313

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:

0.00

Gnomad OTH

AF:

0.000955

GnomAD3 exomes

AF:

0.0000325

AC:

AN:

215238

Hom.:

AF XY:

0.0000256

AC XY:

AN XY:

117012

show subpopulations

Gnomad AFR exome

AF:

0.000158

Gnomad AMR exome

AF:

0.000159

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000623

AC:

AN:

1444402

Hom.:

Cov.:

AF XY:

0.00000418

AC XY:

AN XY:

717148

show subpopulations

Gnomad4 AFR exome

AF:

0.0000908

Gnomad4 AMR exome

AF:

0.000142

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:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.000105

AC:

AN:

152264

Hom.:

Cov.:

AF XY:

0.000121

AC XY:

AN XY:

74380

show subpopulations

Gnomad4 AFR

AF:

0.000313

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000955

Alfa

AF:

0.000166

Hom.:

Bravo

AF:

0.0000907

ExAC

AF:

0.0000331

AC:

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

Jan 19, 2024

The c.70G>A (p.E24K) alteration is located in exon 1 (coding exon 1) of the PIGT gene. This alteration results from a G to A substitution at nucleotide position 70, causing the glutamic acid (E) at amino acid position 24 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Multiple congenital anomalies-hypotonia-seizures syndrome 3

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 16, 2023

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. This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 24 of the PIGT protein (p.Glu24Lys). This variant is present in population databases (rs2741582, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with PIGT-related conditions. 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 PIGT protein function. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.11

BayesDel_addAF

Benign

-0.22

BayesDel_noAF

Benign

-0.30

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.016

T;.;.;.;.;.;.;.;.;.;.;.;.;.;.

Eigen

Benign

-0.38

Eigen_PC

Benign

-0.43

FATHMM_MKL

Benign

0.39

LIST_S2

Uncertain

0.91

D;D;D;D;D;D;D;D;D;D;D;D;D;D;D

M_CAP

Benign

0.016

MetaRNN

Benign

0.096

T;T;T;T;T;T;T;T;T;T;T;T;T;T;T

MetaSVM

Benign

-0.91

MutationAssessor

Benign

1.9

L;L;L;L;.;.;.;.;.;.;.;.;.;L;.

MutationTaster

Benign

1.0

D;N;N;N;N;N

PrimateAI

Uncertain

0.58

PROVEAN

Benign

-0.68

N;N;N;N;.;.;.;.;.;.;.;.;N;.;.

REVEL

Benign

0.17

Sift

Benign

0.37

T;D;T;T;.;.;.;.;.;.;.;.;D;.;.

Sift4G

Benign

0.82

T;T;T;T;.;.;.;.;.;.;.;.;.;.;.

Polyphen

0.025

B;B;.;.;.;.;.;.;.;.;.;.;.;B;.

Vest4

0.51

MVP

0.46

MPC

0.43

ClinPred

0.072

GERP RS

2.5

Varity_R

0.14

gMVP

0.59

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

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