Variant chr6-145627450-A-C details in Genebe, Genetics Data Aggregator

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1PM2PP3

The NM_005670.4(EPM2A):c.962T>G(p.Phe321Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000157 in 1,461,894 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.000016 ( 1 hom. )

Consequence

EPM2A
NM_005670.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 8.95

Variant links:

Genes affected

EPM2A (HGNC:3413): (EPM2A glucan phosphatase, laforin) This gene encodes a dual-specificity phosphatase and may be involved in the regulation of glycogen metabolism. The protein acts on complex carbohydrates to prevent glycogen hyperphosphorylation, thus avoiding the formation of insoluble aggregates. Loss-of-function mutations in this gene have been associated with Lafora disease, a rare, adult-onset recessive neurodegenerative disease, which results in myoclonus epilepsy and usually results in death several years after the onset of symptoms. The disease is characterized by the accumulation of insoluble particles called Lafora bodies, which are derived from glycogen. [provided by RefSeq, Jan 2018]

EPM2A links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM1

In a mutagenesis_site Impairs protein stability. Strongly reduces phosphatase activity. No effect on glycogen binding. (size 0) in uniprot entity EPM2A_HUMAN

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.835

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
EPM2A	NM_005670.4 linkuse as main transcript	c.962T>G	p.Phe321Cys	missense_variant	4/4	ENST00000367519.9	NP_005661.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
EPM2A	ENST00000367519.9 linkuse as main transcript	c.962T>G	p.Phe321Cys	missense_variant	4/4	1	NM_005670.4	ENSP00000356489	P1	O95278-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.0000358

AC:

AN:

251490

Hom.:

AF XY:

0.0000441

AC XY:

AN XY:

135920

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000294

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000157

AC:

AN:

1461894

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

AN XY:

727248

show subpopulations

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:

0.000267

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Progressive myoclonic epilepsy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 25, 2021

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. 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: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has been observed in individual(s) with clinical features of progressive myoclonic epilepsy (PMID: 27574708). This variant is present in population databases (rs772620616, ExAC 0.006%). This sequence change replaces phenylalanine with cysteine at codon 321 of the EPM2A protein (p.Phe321Cys). The phenylalanine residue is highly conserved and there is a large physicochemical difference between phenylalanine and cysteine. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.19

BayesDel_noAF

Pathogenic

0.34

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Benign

0.32

T;.;.;.;.;.

Eigen

Uncertain

0.59

Eigen_PC

Uncertain

0.54

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.90

D;.;.;.;.;D

M_CAP

Pathogenic

0.49

MetaRNN

Pathogenic

0.84

D;D;D;D;D;D

MetaSVM

Pathogenic

1.0

MutationAssessor

Uncertain

2.2

M;.;.;.;.;.

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.60

PROVEAN

Uncertain

-3.0

D;.;.;.;.;.

REVEL

Pathogenic

0.81

Sift

Pathogenic

0.0

D;.;.;.;.;.

Sift4G

Pathogenic

0.0

D;.;D;.;.;.

Polyphen

1.0

D;.;.;.;.;.

Vest4

0.76

MutPred

0.55

Gain of sheet (P = 0.0827);.;.;.;.;.;

MVP

1.0

MPC

1.1

ClinPred

0.79

GERP RS

4.7

gMVP

0.86

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over