rs1554672556

Positions:

• chr9-35091719-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_032634.4(PIGO):​c.2168C>T​(p.Ser723Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,611,918 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 (★★). Synonymous variant affecting the same amino acid position (i.e. S723S) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: PIGO NM_032634.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.91

Genes affected

PIGO (HGNC:23215): (phosphatidylinositol glycan anchor biosynthesis class O) This gene encodes a protein that is involved in glycosylphosphatidylinositol (GPI)-anchor biosynthesis. The GPI-anchor is a glycolipid which contains three mannose molecules in its core backbone. The GPI-anchor is found on many blood cells and serves to anchor proteins to the cell surface. This protein is involved in the transfer of ethanolaminephosphate (EtNP) to the third mannose in GPI. At least three alternatively spliced transcripts encoding two distinct isoforms have been found for this gene. [provided by RefSeq, Jan 2011]

ACMG classification

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, 0.776

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PIGO	NM_032634.4	c.2168C>T	p.Ser723Leu	missense_variant	7/11	ENST00000378617.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PIGO	ENST00000378617.4	c.2168C>T	p.Ser723Leu	missense_variant	7/11	1	NM_032634.4	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152170 Hom.: 0 Cov.: 33

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000480 AC: 7 AN: 1459748 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 726244

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000447

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: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152170 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74346

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: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Feb 18, 2020

Not observed in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Hyperphosphatasia with intellectual disability syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 01, 2022

This sequence change replaces serine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 723 of the PIGO protein (p.Ser723Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with PIGO-related conditions. ClinVar contains an entry for this variant (Variation ID: 540455). 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 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	0.18
BayesDel_addAF	Uncertain	0.10	D
BayesDel_noAF	Benign	-0.090
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.059	T
Eigen	Uncertain	0.24
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	D
M_CAP	Benign	0.032	D
MetaRNN	Pathogenic	0.78	D
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.7	L
MutationTaster	Benign	0.99	D;D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Benign	-1.8	N
REVEL	Benign	0.24
Sift	Uncertain	0.0090	D
Sift4G	Uncertain	0.017	D
Polyphen		0.99	D
Vest4		0.78
MutPred		0.55		Loss of glycosylation at S723 (P = 0.0115);
MVP		0.65
MPC		0.58
ClinPred		0.88	D
GERP RS		5.4
Varity_R		0.17
gMVP		0.61

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: rs1554672556; hg19: chr9-35091716;