rs144204777

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_005670.4(EPM2A):​c.427A>G​(p.Thr143Ala) variant causes a missense change. The variant allele was found at a frequency of 0.0000545 in 1,613,926 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000060 ( 0 hom. )

Consequence

EPM2A
NM_005670.4 missense

Scores

3
6
9

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.84

Publications

2 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 Gene-Disease associations (from GenCC):
  • Lafora disease
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp, PanelApp Australia

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.25350928).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
EPM2ANM_005670.4 linkc.427A>G p.Thr143Ala missense_variant Exon 2 of 4 ENST00000367519.9 NP_005661.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
EPM2AENST00000367519.9 linkc.427A>G p.Thr143Ala missense_variant Exon 2 of 4 1 NM_005670.4 ENSP00000356489.3

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152212
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251364
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000595
AC:
87
AN:
1461714
Hom.:
0
Cov.:
32
AF XY:
0.0000468
AC XY:
34
AN XY:
727154
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44680
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39686
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000782
AC:
87
AN:
1111920
Other (OTH)
AF:
0.00
AC:
0
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
Heterozygous variant carriers
0
5
10
16
21
26
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.00000657
AC:
1
AN:
152212
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74368
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41450
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.00000378
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Progressive myoclonic epilepsy Uncertain:1
Apr 04, 2018
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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 do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with EPM2A-related disease. This variant is present in population databases (rs144204777, ExAC 0.003%). This sequence change replaces threonine with alanine at codon 143 of the EPM2A protein (p.Thr143Ala). The threonine residue is highly conserved and there is a small physicochemical difference between threonine and alanine.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.70
BayesDel_addAF
Uncertain
0.086
D
BayesDel_noAF
Uncertain
-0.010
CADD
Benign
21
DANN
Uncertain
0.97
DEOGEN2
Benign
0.0
.;T;.;.;.;.;.;.;.;.;.
Eigen
Benign
-0.14
Eigen_PC
Benign
-0.018
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Benign
0.83
T;T;.;T;.;.;T;.;T;.;T
M_CAP
Benign
0.038
D
MetaRNN
Benign
0.25
T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.17
D
MutationAssessor
Benign
0.0
.;L;.;L;.;L;L;.;.;.;.
PhyloP100
4.8
PrimateAI
Uncertain
0.75
T
PROVEAN
Benign
0.0
.;N;.;.;.;.;.;.;.;.;.
REVEL
Benign
0.0
Sift
Pathogenic
0.0
.;T;.;.;.;.;.;.;.;.;.
Sift4G
Pathogenic
0.0
.;D;.;T;D;.;.;.;.;.;.
Vest4
0.0
ClinPred
0.28
T
GERP RS
4.4
PromoterAI
0.010
Neutral
gMVP
0.78
Mutation Taster
=41/59
disease causing

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

Other links and lift over

dbSNP: rs144204777; hg19: chr6-146007307; API