17-80110020-A-G

Variant names:

• chr17-80110020-A-G
• rs886043148
• NM_000152.5:c.1402A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 7P and 1B. PM1 PM2 PM5 PP2 BP4

The NM_000152.5(GAA):​c.1402A>G​(p.Ile468Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,460,956 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I468F) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: GAA NM_000152.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.80
• 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, 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

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 12 uncertain in NM_000152.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-80110020-A-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 285589.Status of the report is reviewed_by_expert_panel, 3 stars.
• 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=0.3087886).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GAA	NM_000152.5	c.1402A>G	p.Ile468Val	missense_variant	Exon 9 of 20	ENST00000302262.8	NP_000143.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GAA	ENST00000302262.8	c.1402A>G	p.Ile468Val	missense_variant	Exon 9 of 20	1	NM_000152.5	ENSP00000305692.3

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460956 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726804

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44702

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86244

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52670

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

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111886

Other (OTH) AF: 0.00 AC: 0 AN: 60380

GnomAD4 genome Cov.: 34

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	0.00098	T
BayesDel_noAF	Benign	-0.24
CADD	Benign	19
DANN	Benign	0.72
DEOGEN2	Uncertain	0.50	D;D
Eigen	Benign	-0.36
Eigen_PC	Benign	-0.21
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Benign	0.75	.;T
M_CAP	Uncertain	0.12	D
MetaRNN	Benign	0.31	T;T
MetaSVM	Benign	-0.32	T
MutationAssessor	Benign	0.69	N;N
PhyloP100		4.8
PrimateAI	Uncertain	0.53	T
PROVEAN	Benign	-0.57	N;N
REVEL	Benign	0.24
Sift	Benign	0.48	T;T
Sift4G	Benign	0.42	T;T
Polyphen		0.0090	B;B
Vest4		0.34
MutPred		0.56		Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);
MVP		0.80
MPC		0.12
ClinPred		0.50	T
GERP RS		4.3
Varity_R		0.087
gMVP		0.68
Mutation Taster		=81/19	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

Other links and lift over

dbSNP: rs886043148; hg19: chr17-78083819; COSMIC: COSV56413111; COSMIC: COSV56413111;