rs1555601255

Variant names:

• chr17-80112073-G-A
• rs1555601255
• NM_000152.5:c.1727G>A

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PS3 PM1 PM2 PP2 PP3_Strong PP5

The NM_000152.5(GAA):​c.1727G>A​(p.Gly576Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,682 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 Conflicting classifications of pathogenicity (no stars). ClinVar reports functional evidence for this variant: "SCV006072577: The most pronounced variant effect results in <10% of normal enzyme activity in vitro (e.g. Kroos_2008). PMID:18425781". Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G576S) has been classified as Benign. The gene GAA is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: GAA NM_000152.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 9.30
• Publications: 0 publications found

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, ClinGen, Labcorp Genetics (formerly Invitae), G2P, Laboratory for Molecular Medicine
• 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

ACMG classification

Specifications for GAA are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PS3: PS3 evidence extracted from ClinVar submissions: SCV006072577: The most pronounced variant effect results in <10% of normal enzyme activity in vitro (e.g. Kroos_2008). PMID: 18425781
• PM1: In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 18 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 II, glycogen storage disease due to acid maltase deficiency, infantile onset, glycogen storage disease due to acid maltase deficiency, late-onset.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.997
• PP5: Variant 17-80112073-G-A is Pathogenic according to our data. Variant chr17-80112073-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 526516.

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GAA	NM_000152.5	MANE Select	c.1727G>A	p.Gly576Asp	missense	Exon 12 of 20	NP_000143.2	P10253
	GAA	NM_001079803.3		c.1727G>A	p.Gly576Asp	missense	Exon 13 of 21	NP_001073271.1	P10253
	GAA	NM_001079804.3		c.1727G>A	p.Gly576Asp	missense	Exon 12 of 20	NP_001073272.1	P10253

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GAA	ENST00000302262.8	TSL:1 MANE Select	c.1727G>A	p.Gly576Asp	missense	Exon 12 of 20	ENSP00000305692.3	P10253
	GAA	ENST00000390015.7	TSL:1	c.1727G>A	p.Gly576Asp	missense	Exon 13 of 21	ENSP00000374665.3	P10253
	GAA	ENST00000933406.1		c.1742G>A	p.Gly581Asp	missense	Exon 12 of 20	ENSP00000603465.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461682 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727170

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53322

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111932

Other (OTH) AF: 0.00 AC: 0 AN: 60384

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
1	1	-	Glycogen storage disease, type II (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D
Eigen	Pathogenic	0.95
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.81	D
MetaRNN	Pathogenic	1.0	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.7	H
PhyloP100		9.3
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-6.8	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.99		Loss of catalytic residue at Y575 (P = 0.0929)
MVP		1.0
MPC		0.62
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.99
gMVP		0.98
Mutation Taster		=7/93	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1555601255; hg19: chr17-78085872;