rs200412003

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PP3PM2_SupportingPS3_Supporting

This summary comes from the ClinGen Evidence Repository: The NM_000152.5(GAA):c.1048G>A variant in GAA is a missense variant predicted to cause substitution of valine by methionine at amino acid 350 (p.Val350Met). This variant has been detected in at least 12 individuals, and at least 11 patients with this variant had documented GAA deficiency with activity in the affected range in dried blood spot (Clinical Laboratory data, PMIDs: 25451853, 36310651, 36246652). However, in the absence of clinical symptoms to support that the variant causes Pompe disease, PP4 was not applied. Of those individuals, 1 was homozygous for the variant, and 11 were compound heterozygous for the variant and a pathogenic or likely pathogenic variant in GAA; 2 of those were confirmed in trans by parental testing, including c.-32-13T>G (9 patients, Clinical laboratory data, PMID:25451853, 1 patient confirmed in trans), c.2051C>T (p.Pro684Leu) (1 patient, PMID:36310651, phase unknown), c.1589del (p.Glu530GlyfsTer48) (1 patient, PMID:36246652, phase unknown), and c.2238G>C (p.Trp746Cys) (2 patients, one confirmed in trans and one with a pseudodeficiency allele, Clinical Laboratory data). Due to lack of clinical symptoms in these patients, PM3 is not met at the current time. When expressed in HEK293 cells, GAA enzyme activity was 1.5% of the positive control (Table 3). Western blot revealed faint precursor (110 k Da) and mature (76 kDa) protein bands with lower intensity compared to the positive control, indicating this variant may be impacting GAA protein stability and processing (PS3_Supporting). The highest population minor allele frequency in gnomAD v2.1.1 is 0.00013 (17/1128822 alleles) in the European non-Finnish population, which is lower than the ClinGen Lysosomal Diseases VCEP’s threshold for PM2_Supporting (<0.001), meeting this criterion (PM2_Supporting). The computational predictor REVEL gives a score of 0.878 which is above the threshold of 0.7, evidence that correlates with impact to GAA function (PP3). There is a ClinVar entry for this variant (Variation ID: 555998). In summary, while patients with this variant have been reported with deficiency GAA activity, and the variant has been found in compound heterozygosity with pathogenic and likely pathogenic variants in GAA, the Lysosomal Diseases VCEP concluded that there is insufficient phenotypic evidence to indicate that this variant cuases Pompe disease at this time. Therefore, this variant will be classified as a variant of uncertain significance until further evidence is available. GAA-specific ACMG/AMP criteria applied, as specified by the ClinGen Lysosomal Diseases Variant Curation Expert Panel (Specifications Version 2.0): PS3_Supporting, PP3, PM2_Supporting.(Classification approved by the ClinGen Lysosomal Diseases Variant Curation Expert Panel on March 19, 2024). LINK:https://erepo.genome.network/evrepo/ui/classification/CA8815133/MONDO:0009290/010

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000088 ( 0 hom. )

Consequence

GAA
NM_000152.5 missense

Scores

Clinical Significance

Uncertain significance reviewed by expert panel P:4U:9

Conservation

PhyloP100: 9.38

Publications

9 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

GAA links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PS3

For more information check the summary or visit ClinGen Evidence Repository.

PM2

For more information check the summary or visit ClinGen Evidence Repository.

PP3

For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000152.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
GAA	NM_000152.5	MANE Select	c.1048G>A	p.Val350Met	missense	Exon 6 of 20	NP_000143.2
GAA	NM_001079803.3		c.1048G>A	p.Val350Met	missense	Exon 7 of 21	NP_001073271.1
GAA	NM_001079804.3		c.1048G>A	p.Val350Met	missense	Exon 6 of 20	NP_001073272.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
GAA	ENST00000302262.8	TSL:1 MANE Select	c.1048G>A	p.Val350Met	missense	Exon 6 of 20	ENSP00000305692.3
GAA	ENST00000390015.7	TSL:1	c.1048G>A	p.Val350Met	missense	Exon 7 of 21	ENSP00000374665.3
GAA	ENST00000933406.1		c.1048G>A	p.Val350Met	missense	Exon 6 of 20	ENSP00000603465.1

Frequencies

GnomAD3 genomes

AF:

0.0000657

AC:

AN:

152244

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.0000941

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000103

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000956

AC:

AN:

251022

AF XY:

0.000103

show subpopulations

Gnomad AFR exome

AF:

0.0000618

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.000508

Gnomad NFE exome

AF:

0.0000970

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000876

AC:

128

AN:

1461186

Hom.:

Cov.:

AF XY:

0.0000949

AC XY:

AN XY:

726902

show subpopulations

African (AFR)

AF:

0.0000299

AC:

AN:

33480

American (AMR)

AF:

0.0000224

AC:

AN:

44722

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.0000232

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.000550

AC:

AN:

52724

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.0000818

AC:

AN:

1112008

Other (OTH)

AF:

0.0000662

AC:

AN:

60390

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.476

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000657

AC:

AN:

152244

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74372

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41460

American (AMR)

AF:

0.000131

AC:

AN:

15288

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5194

South Asian (SAS)

AF:

0.00

AC:

AN:

4836

European-Finnish (FIN)

AF:

0.0000941

AC:

AN:

10632

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.000103

AC:

AN:

68046

Other (OTH)

AF:

0.00

AC:

AN:

2090

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.565

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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:

0.000150

Hom.:

Bravo

AF:

0.0000227

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.0000576

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

ClinVar submissions as Germline

Significance:Uncertain significance

Revision:reviewed by expert panel

View on ClinVar

Pathogenic

VUS

Benign

Condition

Glycogen storage disease, type II (9)

not provided (4)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.49

BayesDel_addAF

Uncertain

0.15

BayesDel_noAF

Pathogenic

0.30

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.95

Eigen

Pathogenic

0.98

Eigen_PC

Pathogenic

0.83

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

0.98

M_CAP

Pathogenic

0.84

MetaRNN

Pathogenic

0.94

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

4.6

PhyloP100

9.4

PrimateAI

Uncertain

0.63

PROVEAN

Uncertain

-3.0

REVEL

Pathogenic

0.88

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0

Polyphen

1.0

Vest4

0.81

MVP

0.95

MPC

0.54

ClinPred

0.97

GERP RS

5.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.93

gMVP

0.87

Mutation Taster

=56/44

polymorphism

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.040

Details are displayed if max score is > 0.2

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over