NM_000152.5:c.70G>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 3P and 2B. PM2PP2BP4_Moderate

The NM_000152.5(GAA):​c.70G>A​(p.Ala24Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000205 in 1,613,138 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A24A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

GAA
NM_000152.5 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 1.33

Publications

12 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: Uncertain_significance. The variant received 1 ACMG points.

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.
BP4
Computational evidence support a benign effect (MetaRNN=0.1380167).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GAANM_000152.5 linkc.70G>A p.Ala24Thr missense_variant Exon 2 of 20 ENST00000302262.8 NP_000143.2 P10253

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GAAENST00000302262.8 linkc.70G>A p.Ala24Thr missense_variant Exon 2 of 20 1 NM_000152.5 ENSP00000305692.3 P10253

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152144
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000320
AC:
8
AN:
250032
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000868
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000443
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000205
AC:
30
AN:
1460994
Hom.:
0
Cov.:
31
AF XY:
0.0000193
AC XY:
14
AN XY:
726842
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.0000671
AC:
3
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52602
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000225
AC:
25
AN:
1111972
Other (OTH)
AF:
0.00
AC:
0
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
2
4
5
7
9
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:
0.0000197
AC:
3
AN:
152144
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74304
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41422
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000329
Hom.:
0
Bravo
AF:
0.0000227
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Glycogen storage disease, type II Uncertain:3
Aug 15, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 24 of the GAA protein (p.Ala24Thr). This variant is present in population databases (rs139716763, gnomAD 0.009%). 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: 290440). 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) performed at Invitae indicates that this missense variant is not expected to disrupt 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

- -

Jan 24, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Uncertain:2
Aug 16, 2016
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 23, 2019
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
Jan 10, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.A24T variant (also known as c.70G>A), located in coding exon 1 of the GAA gene, results from a G to A substitution at nucleotide position 70. The alanine at codon 24 is replaced by threonine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. 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
0.080
BayesDel_addAF
Benign
-0.15
T
BayesDel_noAF
Benign
-0.26
CADD
Benign
12
DANN
Uncertain
0.98
DEOGEN2
Benign
0.015
T;.;T;T
Eigen
Benign
-0.98
Eigen_PC
Benign
-0.97
FATHMM_MKL
Benign
0.058
N
LIST_S2
Benign
0.63
T;T;.;T
M_CAP
Benign
0.066
D
MetaRNN
Benign
0.14
T;T;T;T
MetaSVM
Benign
-0.65
T
MutationAssessor
Benign
0.97
.;.;L;L
PhyloP100
1.3
PrimateAI
Benign
0.38
T
PROVEAN
Benign
-0.41
.;.;N;N
REVEL
Benign
0.27
Sift
Benign
0.12
.;.;T;T
Sift4G
Benign
0.60
T;T;T;T
Polyphen
0.0050
.;.;B;B
Vest4
0.18
MVP
0.98
MPC
0.14
ClinPred
0.023
T
GERP RS
0.64
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.028
gMVP
0.61
Mutation Taster
=91/9
polymorphism

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: rs139716763; hg19: chr17-78078455; API