17-39673111-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM1 PM2 BP4

The NM_033419.5(PGAP3):c.839T>C(p.Val280Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000497 in 1,608,970 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: PGAP3 NM_033419.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 5.93

Genes affected

PGAP3 (HGNC:23719): (post-GPI attachment to proteins phospholipase 3) This gene encodes a glycosylphosphatidylinositol (GPI)-specific phospholipase that primarily localizes to the Golgi apparatus. This ubiquitously expressed gene is predicted to encode a seven-transmembrane protein that removes unsaturated fatty acids from the sn-2 position of GPI. The remodeling of the constituent fatty acids on GPI is thought to be important for the proper association between GPI-anchored proteins and lipid rafts. The tethering of proteins to plasma membranes via posttranslational GPI-anchoring is thought to play a role in protein sorting and trafficking. Mutations in this gene cause an autosomal recessive form of neurologic hyperphosphatasia with cognitive disability (HPMRS4). Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jul 2017]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_033419.5
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.40679926).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PGAP3	NM_033419.5	c.839T>C	p.Val280Ala	missense_variant	7/8	ENST00000300658.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PGAP3	ENST00000300658.9	c.839T>C	p.Val280Ala	missense_variant	7/8	1	NM_033419.5	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152124 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

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: 0.00

GnomAD4 exome AF: 0.00000412 AC: 6 AN: 1456728 Hom.: 0 Cov.: 34 AF XY: 0.00000276 AC XY: 2 AN XY: 724048

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: 0.00

Gnomad4 OTH exome AF: 0.0000996

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152242 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74436

Gnomad4 AFR AF: 0.00

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: 0.000474

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Jan 27, 2022	In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Apr 09, 2022	This sequence change replaces valine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 280 of the PGAP3 protein (p.Val280Ala). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with PGAP3-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: "Tolerated"; 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	Uncertain	0.37
BayesDel_addAF	Uncertain	0.039	T
BayesDel_noAF	Benign	-0.18
Cadd	Pathogenic	26
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.61	D;.;.
Eigen	Uncertain	0.36
Eigen_PC	Uncertain	0.42
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.87	D;D;D
M_CAP	Benign	0.0098	T
MetaRNN	Benign	0.41	T;T;T
MetaSVM	Benign	-0.89	T
MutationAssessor	Benign	1.3	L;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.56	T
PROVEAN	Uncertain	-3.0	D;D;D
REVEL	Benign	0.18
Sift	Uncertain	0.010	D;D;D
Sift4G	Uncertain	0.022	D;T;D
Polyphen		0.93	P;P;.
Vest4		0.50
MutPred		0.53		Loss of stability (P = 0.0898);.;.;
MVP		0.59
MPC		0.70
ClinPred		0.95	D
GERP RS		5.5
Varity_R		0.26
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

Other links and lift over

dbSNP: rs1044944497; hg19: chr17-37829364;