rs111545736

chr4-527200-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_001127178.3(PIGG):c.2231C>T(p.Pro744Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000804 in 1,603,668 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. P744P) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000092 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000079 (0 hom.)
• Consequence: PIGG NM_001127178.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.93

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PIGG	NM_001127178.3	c.2231C>T	p.Pro744Leu	missense_variant	10/13	ENST00000453061.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PIGG	ENST00000453061.7	c.2231C>T	p.Pro744Leu	missense_variant	10/13	1	NM_001127178.3	P4

Frequencies

GnomAD3 genomes AF: 0.0000789 AC: 12 AN: 152184 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000193

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000620

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000133 AC: 32 AN: 240428 Hom.: 0 AF XY: 0.000169 AC XY: 22 AN XY: 130220

Gnomad AFR exome AF: 0.000188

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000895

Gnomad FIN exome AF: 0.0000475

Gnomad NFE exome AF: 0.00000921

Gnomad OTH exome AF: 0.000172

GnomAD4 exome AF: 0.0000792 AC: 115 AN: 1451366 Hom.: 0 Cov.: 32 AF XY: 0.0000999 AC XY: 72 AN XY: 720972

Gnomad4 AFR exome AF: 0.000544

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000788

Gnomad4 FIN exome AF: 0.0000188

Gnomad4 NFE exome AF: 0.0000154

Gnomad4 OTH exome AF: 0.000200

GnomAD4 genome AF: 0.0000919 AC: 14 AN: 152302 Hom.: 0 Cov.: 32 AF XY: 0.0000940 AC XY: 7 AN XY: 74474

Gnomad4 AFR AF: 0.000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000621

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000982

ESP6500AA AF: 0.000227 AC: 1

ESP6500EA AF: 0.00 AC: 0

ExAC AF: 0.000132 AC: 16

Asia WGS AF: 0.00144 AC: 5 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability, autosomal recessive 53 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 03, 2023

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 744 of the PIGG protein (p.Pro744Leu). This variant is present in population databases (rs111545736, gnomAD 0.09%). 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: 542881). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on PIGG protein function. 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	0.12
BayesDel_addAF	Benign	-0.054	T
BayesDel_noAF	Uncertain	0.070
Cadd	Uncertain	24
Dann	Uncertain	1.0
Eigen	Uncertain	0.49
Eigen_PC	Uncertain	0.42
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.87	D;D;D;D
M_CAP	Benign	0.036	D
MetaRNN	Uncertain	0.68	D;D;D;D
MetaSVM	Benign	-1.1	T
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-6.2	D;D;D;D
REVEL	Uncertain	0.42
Sift	Uncertain	0.0030	D;D;D;D
Sift4G	Uncertain	0.011	D;D;D;D
Polyphen		1.0	D;D;.;D
Vest4		0.90
MVP		0.52
MPC		0.70
ClinPred		0.57	D
GERP RS		6.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.35
gMVP		0.69

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

Other links and lift over

dbSNP: rs111545736; hg19: chr4-520989;