rs778032599

Variant names:

• chr17-80118809-A-G
• rs778032599
• NM_000152.5:c.2799+4A>G

Your query was ambiguous. Multiple possible variants found:

• chr17-80118809-A-G
• chr17-80118809-A-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PP3 PM2_Supporting PM3 PP4_Moderate

This summary comes from the ClinGen Evidence Repository: The NM_000152.5:c.2799+4A>G is located in the donor splice site region of intron 19, the final intron of GAA. The computational splicing predictor SpliceAI gives a score of 0.62 for donor loss, predicting that the variant disrupts the donor splice site of this intron (PP3). Two individuals with Pompe disease have been reported to have this variant; one has documentation of deficient GAA activity and is on enzyme replacement therapy (PMID:26873529) (PP4_Moderate), and the second patient has limb girdle muscular dystrophy (PMID:30564623). Both individuals are compound heterozygous for this variant and another variant in GAA that has been classified as pathogenic by the ClinGen Lysosomal Diseases VCEP, either c.1548G>A (p.Trp516Ter) (PMID:26873529) or c.2501_2502delCA (PMID:30564623); the phase is unknown in each case (PM3). The highest population minor allele frequency in gnomAD v2.1.1 is 0.00006 (1/16172 alleles) in the African population, which is lower than the ClinGen Lysosomal Diseases VCEP’s threshold for PM2_Supporting (<0.001), meeting this criterion (PM2_Supporting). Additional variants in this splice region have been identified, including c.2799+2C>T, c.2799+2C>A, and c.2799+5G>A (PMID:28265479); all currently classified by the ClinGen LD VCEP as variants of uncertain significance. In summary, this variant meets the criteria to be classified as likley pathogenic for Pompe disease. GAA-specific ACMG/AMP criteria met, as specified by the ClinGen Lysosomal Diseases Variant Curation Expert Panel (Specifications Version 2.0): PM3, PP4_Moderate, PP3, PM2_Supporting.(Classification approved by the ClinGen Lysosomal Diseases VCEP, June 27, 2023) LINK:https://erepo.genome.network/evrepo/ui/classification/CA8815855/MONDO:0009290/010

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: GAA NM_000152.5 splice_region, intron
• Clinical Significance: Likely pathogenic reviewed by expert panel P:5 U:4
• Conservation: PhyloP100: 1.79
• 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: G2P, ClinGen, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PM3: For more information check the summary or visit ClinGen Evidence Repository.
• PP3: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: 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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GAA	NM_000152.5	MANE Select	c.2799+4A>G		splice_region intron	N/A	NP_000143.2	P10253
	GAA	NM_001079803.3		c.2799+4A>G		splice_region intron	N/A	NP_001073271.1	P10253
	GAA	NM_001079804.3		c.2799+4A>G		splice_region intron	N/A	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.2799+4A>G		splice_region intron	N/A	ENSP00000305692.3	P10253
	GAA	ENST00000390015.7	TSL:1	c.2799+4A>G		splice_region intron	N/A	ENSP00000374665.3	P10253
	GAA	ENST00000933406.1		c.2814+4A>G		splice_region intron	N/A	ENSP00000603465.1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152174 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000400 AC: 1 AN: 249970 AF XY: 0.00

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: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000144 AC: 21 AN: 1460630 Hom.: 0 Cov.: 33 AF XY: 0.0000124 AC XY: 9 AN XY: 726590

African (AFR) AF: 0.0000299 AC: 1 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52202

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

European-Non Finnish (NFE) AF: 0.0000180 AC: 20 AN: 1111988

Other (OTH) AF: 0.00 AC: 0 AN: 60376

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152174 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74340

African (AFR) AF: 0.0000724 AC: 3 AN: 41452

American (AMR) AF: 0.00 AC: 0 AN: 15278

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68028

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000227

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
5	2	-	Glycogen storage disease, type II (7)
-	2	-	not provided (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.43
CADD	Benign	14
DANN	Benign	0.76
PhyloP100		1.8
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.62		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.62		Position offset: -4

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs778032599;

hg19: chr17-78092608;

COSMIC: COSV56406769;

COSMIC: COSV56406769;