Genetic Variant PIGG:p.Met344Thr (chr4-516102-T-C) – ACMG Classification: Uncertain_significance (3 pts)

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PM2PM5BP4

The NM_001127178.3(PIGG):c.1031T>C(p.Met344Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,696 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M344L) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

PIGG
NM_001127178.3 missense

Scores

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 6.36

Publications

2 publications found

Variant links:

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]

PIGG Gene-Disease associations (from GenCC):

intellectual disability, autosomal recessive 53
Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)

PIGG links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr4-516101-A-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 807655.

BP4

Computational evidence support a benign effect (MetaRNN=0.33550173).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001127178.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
PIGG	NM_001127178.3	MANE Select	c.1031T>C	p.Met344Thr	missense	Exon 6 of 13	NP_001120650.1
PIGG	NM_001345988.2		c.2T>C	p.Met1?	start_lost	Exon 5 of 12	NP_001332917.1
PIGG	NM_017733.5		c.1031T>C	p.Met344Thr	missense	Exon 6 of 13	NP_060203.3

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
PIGG	ENST00000453061.7	TSL:1 MANE Select	c.1031T>C	p.Met344Thr	missense	Exon 6 of 13	ENSP00000415203.2
PIGG	ENST00000383028.8	TSL:1	c.632T>C	p.Met211Thr	missense	Exon 4 of 11	ENSP00000372494.4
PIGG	ENST00000509768.1	TSL:1	c.764T>C	p.Met255Thr	missense	Exon 6 of 8	ENSP00000421550.1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD2 exomes

AF:

0.00000398

AC:

AN:

251492

AF XY:

0.00000736

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

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:

AN:

1461696

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727176

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33474

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26134

East Asian (EAS)

AF:

0.0000252

AC:

AN:

39696

South Asian (SAS)

AF:

0.00

AC:

AN:

86250

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53416

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1111844

Other (OTH)

AF:

0.00

AC:

AN:

60390

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.425

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

Cov.:

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.19

BayesDel_addAF

Benign

-0.19

BayesDel_noAF

Benign

-0.34

CADD

Benign

(source)

DANN

Benign

0.44

DEOGEN2

Benign

0.078

Eigen

Benign

-0.19

Eigen_PC

Benign

-0.10

FATHMM_MKL

Uncertain

0.92

LIST_S2

Uncertain

0.89

M_CAP

Benign

0.0066

MetaRNN

Benign

0.34

MetaSVM

Benign

-1.0

MutationAssessor

Uncertain

2.3

PhyloP100

6.4

PrimateAI

Benign

0.42

PROVEAN

Uncertain

-2.5

REVEL

Benign

0.17

Sift

Benign

0.061

Sift4G

Benign

0.15

Polyphen

0.14

Vest4

0.47

MutPred

0.43

Gain of relative solvent accessibility (P = 0.0098)

MVP

0.61

MPC

0.25

ClinPred

0.65

GERP RS

4.9

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.22

gMVP

0.54

Mutation Taster

=61/39

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

ClinVar

Computational scores

Splicing

Publications

Other links and lift over