chr21-37065654-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_153682.3(PIGP):​c.333A>T​(p.Leu111Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000124 in 1,613,358 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 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

PIGP
NM_153682.3 missense

Scores

2
10
7

Clinical Significance

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

Conservation

PhyloP100: 0.447
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.913

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
PIGPNM_153682.3 linkuse as main transcriptc.333A>T p.Leu111Phe missense_variant 5/5 ENST00000360525.9 NP_710149.1 P57054-2
PIGPNM_153681.2 linkuse as main transcriptc.405A>T p.Leu135Phe missense_variant 4/4 NP_710148.1 P57054-1
PIGPNM_001320480.2 linkuse as main transcriptc.333A>T p.Leu111Phe missense_variant 5/5 NP_001307409.1 P57054-2
PIGPNM_016430.4 linkuse as main transcriptc.255A>T p.Leu85Phe missense_variant 6/6 NP_057514.2 P57054-3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
PIGPENST00000360525.9 linkuse as main transcriptc.333A>T p.Leu111Phe missense_variant 5/51 NM_153682.3 ENSP00000353719.3 P57054-2

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152194
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000217
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000402
AC:
1
AN:
248978
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
134778
show subpopulations
Gnomad AFR exome
AF:
0.0000615
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000753
AC:
11
AN:
1461164
Hom.:
0
Cov.:
30
AF XY:
0.00000550
AC XY:
4
AN XY:
726906
show subpopulations
Gnomad4 AFR exome
AF:
0.000269
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:
9.00e-7
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152194
Hom.:
0
Cov.:
32
AF XY:
0.0000672
AC XY:
5
AN XY:
74350
show subpopulations
Gnomad4 AFR
AF:
0.000217
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:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.00000824
AC:
1

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 submitterclinical testingAmbry GeneticsMar 30, 2024The c.405A>T (p.L135F) 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 405, causing the leucine (L) at amino acid position 135 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 submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 30, 2022This sequence change replaces leucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 135 of the PIGP protein (p.Leu135Phe). This variant is present in population databases (rs763288452, gnomAD 0.01%). 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: "Probably Damaging"; Align-GVGD: "Class C15"). 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
Uncertain
0.37
BayesDel_addAF
Benign
-0.084
T
BayesDel_noAF
Benign
-0.18
CADD
Benign
20
DANN
Uncertain
1.0
DEOGEN2
Benign
0.11
.;T;.;.;.
Eigen
Uncertain
0.39
Eigen_PC
Uncertain
0.30
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Uncertain
0.86
.;D;.;D;D
M_CAP
Benign
0.025
T
MetaRNN
Pathogenic
0.91
D;D;D;D;D
MetaSVM
Benign
-0.87
T
MutationAssessor
Pathogenic
3.1
.;M;.;.;.
PrimateAI
Benign
0.47
T
PROVEAN
Uncertain
-2.8
D;D;D;D;D
REVEL
Uncertain
0.34
Sift
Uncertain
0.0090
D;D;D;D;D
Sift4G
Uncertain
0.024
D;D;D;D;D
Polyphen
1.0
.;D;.;.;.
Vest4
0.50
MutPred
0.85
.;Loss of stability (P = 0.0633);.;.;.;
MVP
0.41
MPC
0.064
ClinPred
0.94
D
GERP RS
1.9
Varity_R
0.19
gMVP
0.87

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.

Other links and lift over

dbSNP: rs763288452; hg19: chr21-38437954; API