4-521848-G-C

Position:

• chr4-521848-G-C

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_001127178.3(PIGG):​c.1521G>C​(p.Ala507=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. A507A) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: PIGG NM_001127178.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.23

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 Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BP7: Synonymous conserved (PhyloP=-1.23 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PIGG	NM_001127178.3	c.1521G>C	p.Ala507=	synonymous_variant	8/13	ENST00000453061.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PIGG	ENST00000453061.7	c.1521G>C	p.Ala507=	synonymous_variant	8/13	1	NM_001127178.3	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	0.37
DANN	Benign	0.44

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr4-515637; COSMIC: COSV99574272; COSMIC: COSV99574272;