6-145735356-C-T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP4

The NM_005670.4(EPM2A):​c.143G>A​(p.Gly48Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000395 in 1,309,652 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00021 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00042 ( 1 hom. )

Consequence

EPM2A
NM_005670.4 missense

Scores

2
5
12

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 0.584

Publications

0 publications found
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-DT (HGNC:48990): (EPM2A divergent transcript)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -1 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.41180414).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
EPM2ANM_005670.4 linkc.143G>A p.Gly48Asp missense_variant Exon 1 of 4 ENST00000367519.9 NP_005661.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
EPM2AENST00000367519.9 linkc.143G>A p.Gly48Asp missense_variant Exon 1 of 4 1 NM_005670.4 ENSP00000356489.3

Frequencies

GnomAD3 genomes
AF:
0.000214
AC:
32
AN:
149732
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000971
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000664
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000268
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000110
AC:
4
AN:
36458
AF XY:
0.0000900
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000386
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000132
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000418
AC:
485
AN:
1159920
Hom.:
1
Cov.:
35
AF XY:
0.000423
AC XY:
240
AN XY:
566996
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
22946
American (AMR)
AF:
0.000274
AC:
4
AN:
14584
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
15970
East Asian (EAS)
AF:
0.00
AC:
0
AN:
23072
South Asian (SAS)
AF:
0.00
AC:
0
AN:
47050
European-Finnish (FIN)
AF:
0.000265
AC:
7
AN:
26396
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
3148
European-Non Finnish (NFE)
AF:
0.000477
AC:
459
AN:
961400
Other (OTH)
AF:
0.000331
AC:
15
AN:
45354
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.507
Heterozygous variant carriers
0
28
55
83
110
138
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
24
48
72
96
120
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000214
AC:
32
AN:
149732
Hom.:
0
Cov.:
33
AF XY:
0.000205
AC XY:
15
AN XY:
73034
show subpopulations
African (AFR)
AF:
0.0000971
AC:
4
AN:
41194
American (AMR)
AF:
0.000664
AC:
10
AN:
15058
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3420
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5114
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
9708
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.000268
AC:
18
AN:
67134
Other (OTH)
AF:
0.00
AC:
0
AN:
2058
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.509
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000356
Hom.:
0
Bravo
AF:
0.000298

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Mar 05, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis indicates that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Sep 18, 2018
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Lafora disease Uncertain:1
Mar 30, 2021
Center for Genomics, Ann and Robert H. Lurie Children's Hospital of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

EPM2A NM_005670.3 exon 1 p.Gly48Asp (c.143G>A):This variant has not been reported in the literature but is present in 8/29388 European alleles in the Genome Aggregation Database (http://gnomad.broadinstitute.org/). This variant is present in ClinVar (Variation ID:377829). Evolutionary conservation and computational predictive tools for this variant are limited or unavailable. In summary, data on this variant is insufficient for disease classification. Therefore, the clinical significance of this variant is uncertain. -

Inborn genetic diseases Uncertain:1
Jan 24, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.143G>A (p.G48D) alteration is located in exon 1 (coding exon 1) of the EPM2A gene. This alteration results from a G to A substitution at nucleotide position 143, causing the glycine (G) at amino acid position 48 to be replaced by an aspartic acid (D). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Progressive myoclonic epilepsy Uncertain:1
Nov 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 48 of the EPM2A protein (p.Gly48Asp). This variant is present in population databases (no rsID available, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with EPM2A-related conditions. ClinVar contains an entry for this variant (Variation ID: 377829). 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: "Benign"; 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
0.16
BayesDel_addAF
Benign
-0.068
T
BayesDel_noAF
Uncertain
-0.010
CADD
Benign
16
DANN
Benign
0.97
DEOGEN2
Uncertain
0.44
T;.;.;.
Eigen
Benign
-0.31
Eigen_PC
Benign
-0.29
FATHMM_MKL
Benign
0.71
D
LIST_S2
Benign
0.62
T;T;.;T
M_CAP
Pathogenic
0.61
D
MetaRNN
Benign
0.41
T;T;T;T
MetaSVM
Uncertain
-0.15
T
MutationAssessor
Benign
0.55
N;N;N;N
PhyloP100
0.58
PrimateAI
Pathogenic
0.86
D
PROVEAN
Benign
-1.0
N;.;.;.
REVEL
Uncertain
0.49
Sift
Uncertain
0.023
D;.;.;.
Sift4G
Benign
0.11
T;T;.;.
Polyphen
0.11
B;P;P;.
Vest4
0.18
MutPred
0.56
Gain of relative solvent accessibility (P = 0.0479);Gain of relative solvent accessibility (P = 0.0479);Gain of relative solvent accessibility (P = 0.0479);Gain of relative solvent accessibility (P = 0.0479);
MVP
0.95
MPC
0.34
ClinPred
0.078
T
GERP RS
2.5
PromoterAI
-0.039
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
2.6
gMVP
0.44
Mutation Taster
=88/12
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs946076987; hg19: chr6-146056492; COSMIC: COSV105281611; COSMIC: COSV105281611; API