1-160030778-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_145167.3(PIGM):c.962C>A(p.Thr321Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T321A) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PIGM NM_145167.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.53

Genes affected

PIGM (HGNC:18858): (phosphatidylinositol glycan anchor biosynthesis class M) This gene encodes a transmembrane protein that is located in the endoplasmic reticulum and is involved in GPI-anchor biosynthesis. The glycosylphosphatidylinositol (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 gene encodes a mannosyltransferase, GPI-MT-I, that transfers the first mannose to GPI on the lumenal side of the endoplasmic reticulum. [provided by RefSeq, Jul 2008]

KCNJ10 (HGNC:6256): (potassium inwardly rectifying channel subfamily J member 10) This gene encodes a member of the inward rectifier-type potassium channel family, characterized by having a greater tendency to allow potassium to flow into, rather than out of, a cell. The encoded protein may form a heterodimer with another potassium channel protein and may be responsible for the potassium buffering action of glial cells in the brain. Mutations in this gene have been associated with seizure susceptibility of common idiopathic generalized epilepsy syndromes. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PIGM	NM_145167.3	c.962C>A	p.Thr321Lys	missense_variant	1/1	ENST00000368090.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PIGM	ENST00000368090.5	c.962C>A	p.Thr321Lys	missense_variant	1/1		NM_145167.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

PIGM-related disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Aug 18, 2022

The PIGM c.962C>A variant is predicted to result in the amino acid substitution p.Thr321Lys. To our knowledge, this variant has not been reported in the literature or in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.27
Cadd	Pathogenic	32
Dann	Uncertain	0.99
DEOGEN2	Uncertain	0.43	T
Eigen	Pathogenic	0.93
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.89	D
M_CAP	Uncertain	0.14	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	0.040	D
MutationAssessor	Pathogenic	3.7	H
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-6.0	D
REVEL	Pathogenic	0.74
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.89
MutPred		0.93		Gain of ubiquitination at T321 (P = 0.0311);
MVP		0.86
MPC		1.2
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.97
gMVP		0.90

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-160000568;