rs1555600235

Variant names:

• chr17-80108816-CATG-C
• rs1555600235
• NM_000152.5:c.1320_1322delGAT

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1 PM2 PM4_Supporting

The NM_000152.5(GAA):​c.1320_1322delGAT​(p.Met440del) variant causes a disruptive inframe deletion change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: GAA NM_000152.5 disruptive_inframe_deletion
• Clinical Significance: Uncertain significance reviewed by expert panel P:3 U:2
• Conservation: PhyloP100: 7.49
• Publications: 1 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: Uncertain_significance. The variant received 5 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, 15 uncertain in NM_000152.5
• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_000152.5. Strenght limited to Supporting due to length of the change: 1aa.

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.1320_1322delGAT	p.Met440del	disruptive_inframe_deletion	Exon 8 of 20	NP_000143.2
	GAA	NM_001079803.3		c.1320_1322delGAT	p.Met440del	disruptive_inframe_deletion	Exon 9 of 21	NP_001073271.1
	GAA	NM_001079804.3		c.1320_1322delGAT	p.Met440del	disruptive_inframe_deletion	Exon 8 of 20	NP_001073272.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GAA	ENST00000302262.8	TSL:1 MANE Select	c.1320_1322delGAT	p.Met440del	disruptive_inframe_deletion	Exon 8 of 20	ENSP00000305692.3
	GAA	ENST00000390015.7	TSL:1	c.1320_1322delGAT	p.Met440del	disruptive_inframe_deletion	Exon 9 of 21	ENSP00000374665.3
	GAA	ENST00000933406.1		c.1320_1322delGAT	p.Met440del	disruptive_inframe_deletion	Exon 8 of 20	ENSP00000603465.1

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
2	2	-	Glycogen storage disease, type II (4)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.5
Mutation Taster		=61/39	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs1555600235; hg19: chr17-78082615;