rs758334520

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1PM2PP2PP3_Moderate

The NM_000152.5(GAA):​c.1198G>A​(p.Val400Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000372 in 1,612,592 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. V400V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000037 ( 0 hom. )

Consequence

GAA
NM_000152.5 missense

Scores

4
10
5

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:8

Conservation

PhyloP100: 6.12

Publications

4 publications found
Variant links:
Genes affected
GAA (HGNC:4065): (alpha glucosidase) This gene encodes lysosomal alpha-glucosidase, which is essential for the degradation of glycogen to glucose in lysosomes. The encoded preproprotein is proteolytically processed to generate multiple intermediate forms and the mature form of the enzyme. Defects in this gene are the cause of glycogen storage disease II, also known as Pompe's disease, which is an autosomal recessive disorder with a broad clinical spectrum. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2016]
GAA Gene-Disease associations (from GenCC):
  • glycogen storage disease II
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), PanelApp Australia, ClinGen, G2P
  • glycogen storage disease due to acid maltase deficiency, infantile onset
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • glycogen storage disease due to acid maltase deficiency, late-onset
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

PM1
In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_000152.5
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 201 curated pathogenic missense variants (we use a threshold of 10). The gene has 50 curated benign missense variants. Gene score misZ: -0.63308 (below the threshold of 3.09). Trascript score misZ: -0.32889 (below the threshold of 3.09). GenCC associations: The gene is linked to glycogen storage disease due to acid maltase deficiency, infantile onset, glycogen storage disease II, glycogen storage disease due to acid maltase deficiency, late-onset.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.895

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GAANM_000152.5 linkc.1198G>A p.Val400Ile missense_variant Exon 8 of 20 ENST00000302262.8 NP_000143.2 P10253

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GAAENST00000302262.8 linkc.1198G>A p.Val400Ile missense_variant Exon 8 of 20 1 NM_000152.5 ENSP00000305692.3 P10253

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152198
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000524
AC:
13
AN:
247946
AF XY:
0.0000593
show subpopulations
Gnomad AFR exome
AF:
0.000127
Gnomad AMR exome
AF:
0.000174
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000937
Gnomad NFE exome
AF:
0.0000179
Gnomad OTH exome
AF:
0.000166
GnomAD4 exome
AF:
0.0000370
AC:
54
AN:
1460394
Hom.:
0
Cov.:
38
AF XY:
0.0000440
AC XY:
32
AN XY:
726500
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000895
AC:
4
AN:
44680
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86246
European-Finnish (FIN)
AF:
0.0000575
AC:
3
AN:
52132
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000333
AC:
37
AN:
1111930
Other (OTH)
AF:
0.000149
AC:
9
AN:
60336
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.499
Heterozygous variant carriers
0
4
8
13
17
21
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152198
Hom.:
0
Cov.:
33
AF XY:
0.0000672
AC XY:
5
AN XY:
74354
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000752
Hom.:
0
Bravo
AF:
0.0000567
ExAC
AF:
0.0000660
AC:
8
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Glycogen storage disease, type II Uncertain:4
Jan 24, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Feb 22, 2022
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

Oct 04, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 400 of the GAA protein (p.Val400Ile). This variant is present in population databases (rs758334520, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with GAA-related conditions. ClinVar contains an entry for this variant (Variation ID: 566063). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on GAA protein function. 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. -

Sep 05, 2021
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:3
Nov 12, 2020
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

GAA: PM2 -

Apr 06, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Has not been previously reported in peer-reviewed literature as pathogenic or benign to our knowledge. However, in an abstract by Dib et al. (2014), p.(V400I) was reported in a mother and daughter with a distal myopathy presentation, however a second GAA variant was not reported.; In silico analysis supports that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: Dib_2014_Abstract) -

Cardiovascular phenotype Uncertain:1
Mar 01, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.V400I variant (also known as c.1198G>A), located in coding exon 7 of the GAA gene, results from a G to A substitution at nucleotide position 1198. The valine at codon 400 is replaced by isoleucine, an amino acid with highly similar properties. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Benign
-0.020
T
BayesDel_noAF
Uncertain
-0.030
CADD
Benign
23
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.71
D;D
Eigen
Uncertain
0.30
Eigen_PC
Benign
0.17
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.96
.;D
M_CAP
Uncertain
0.26
D
MetaRNN
Pathogenic
0.89
D;D
MetaSVM
Pathogenic
0.90
D
MutationAssessor
Pathogenic
3.1
M;M
PhyloP100
6.1
PrimateAI
Uncertain
0.51
T
PROVEAN
Benign
-0.99
N;N
REVEL
Uncertain
0.50
Sift
Uncertain
0.011
D;D
Sift4G
Uncertain
0.013
D;D
Polyphen
0.96
D;D
Vest4
0.51
MutPred
0.79
Gain of catalytic residue at L405 (P = 0.0811);Gain of catalytic residue at L405 (P = 0.0811);
MVP
0.96
MPC
0.44
ClinPred
0.51
D
GERP RS
2.9
Varity_R
0.41
gMVP
0.69
Mutation Taster
=75/25
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs758334520; hg19: chr17-78082499; COSMIC: COSV108129461; COSMIC: COSV108129461; API