17-39672847-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_033419.5(PGAP3):c.919C>G(p.Leu307Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. L307L) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PGAP3 NM_033419.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.89

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 2 ACMG points.

• PM1: In a chain Post-GPI attachment to proteins factor 3 (size 299) in uniprot entity PGAP3_HUMAN there are 30 pathogenic changes around while only 12 benign (71%) in NM_033419.5
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.24421751).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PGAP3	NM_033419.5	c.919C>G	p.Leu307Val	missense_variant	8/8	ENST00000300658.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PGAP3	ENST00000300658.9	c.919C>G	p.Leu307Val	missense_variant	8/8	1	NM_033419.5	P1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250512 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135504

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 6.84e-7 AC: 1 AN: 1461816 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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 Cov.: 34

Bravo AF: 0.00000378

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.00 AC: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 11, 2022

This sequence change replaces leucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 307 of the PGAP3 protein (p.Leu307Val). This variant is present in population databases (rs769690688, gnomAD 0.003%). 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: "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	0.10
BayesDel_addAF	Benign	-0.060	T
BayesDel_noAF	Benign	-0.24
Cadd	Benign	22
Dann	Uncertain	0.99
DEOGEN2	Benign	0.065	T;.;.
Eigen	Benign	0.085
Eigen_PC	Benign	0.040
FATHMM_MKL	Uncertain	0.79	D
LIST_S2	Uncertain	0.93	D;D;D
M_CAP	Benign	0.024	T
MetaRNN	Benign	0.24	T;T;T
MetaSVM	Benign	-0.76	T
MutationAssessor	Uncertain	2.7	M;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Benign	0.48	T
PROVEAN	Benign	-1.5	N;N;N
REVEL	Uncertain	0.50
Sift	Benign	0.076	T;D;T
Sift4G	Benign	0.10	T;T;T
Polyphen		1.0	D;D;.
Vest4		0.18
MutPred		0.47		Loss of helix (P = 0.0558);.;.;
MVP		0.47
MPC		1.1
ClinPred		0.80	D
GERP RS		2.1
Varity_R		0.44
gMVP		0.33

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: rs769690688; hg19: chr17-37829100;