17-80116996-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_000152.5(GAA):​c.2218G>A​(p.Val740Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,440 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 (★★).

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

GAA
NM_000152.5 missense

Scores

2
9
8

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 1.20
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.871

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GAANM_000152.5 linkuse as main transcriptc.2218G>A p.Val740Met missense_variant 16/20 ENST00000302262.8 NP_000143.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GAAENST00000302262.8 linkuse as main transcriptc.2218G>A p.Val740Met missense_variant 16/201 NM_000152.5 ENSP00000305692 P1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD3 exomes
AF:
0.00000399
AC:
1
AN:
250940
Hom.:
0
AF XY:
0.00000737
AC XY:
1
AN XY:
135774
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000883
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461440
Hom.:
0
Cov.:
30
AF XY:
0.00000275
AC XY:
2
AN XY:
727034
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:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000180
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
33
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Glycogen storage disease, type II Uncertain:3
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Uncertain significance, criteria provided, single submitterclinical testingGenome-Nilou LabSep 05, 2021- -
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpMay 27, 2022This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 740 of the GAA protein (p.Val740Met). This variant is present in population databases (rs752122499, gnomAD 0.0009%). 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: 456395). 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 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. -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsDec 24, 2021The p.V740M variant (also known as c.2218G>A), located in coding exon 15 of the GAA gene, results from a G to A substitution at nucleotide position 2218. The valine at codon 740 is replaced by methionine, an amino acid with highly similar properties. This amino acid position is conserved. 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
Uncertain
0.099
D
BayesDel_noAF
Benign
-0.10
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.77
D;D
Eigen
Uncertain
0.45
Eigen_PC
Uncertain
0.45
FATHMM_MKL
Benign
0.71
D
LIST_S2
Benign
0.75
.;T
M_CAP
Pathogenic
0.30
D
MetaRNN
Pathogenic
0.87
D;D
MetaSVM
Uncertain
0.49
D
MutationAssessor
Benign
2.0
M;M
MutationTaster
Benign
0.70
N;N
PrimateAI
Benign
0.43
T
PROVEAN
Benign
-1.8
N;N
REVEL
Uncertain
0.56
Sift
Uncertain
0.013
D;D
Sift4G
Uncertain
0.0040
D;D
Polyphen
0.92
P;P
Vest4
0.61
MutPred
0.68
Gain of disorder (P = 0.0789);Gain of disorder (P = 0.0789);
MVP
0.98
MPC
0.45
ClinPred
0.79
D
GERP RS
4.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.32
gMVP
0.65

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.

Other links and lift over

dbSNP: rs752122499; hg19: chr17-78090795; API