rs1344266804

Positions:

• chr17-80117675-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP4 PM3_Supporting

This summary comes from the ClinGen Evidence Repository: The NM_000152.5:c.2407C>T (p.Gln803Ter) variant in GAA is a nonsense variant predicted to cause a premature stop codon in biologically-relevant-exon 17 (out of 20 exons), leading to nonsense mediated decay in a gene in which loss-of-function is an established disease mechanism (PVS1). One patient with late onset Pompe disease with this variant and treated by enzyme replacement therapy has been reported (PP4). This individual is compound heterozygous for the variant and "IVS 0-45T>G" (assumed to be c.-32-13T>G), a pathogenic variant in GAA, phase unknown (PMID:26572913) (PM3_Supporting). Two additional patients have been reported to be compound heterozygous for p.Gln803Ter but the cDNA change provided is incorrect and thus this data was not included (PMID:21940687). The highest population minor allele frequency in gnomAD v2.1.1 is 0.00001 (1/111412 alleles) in the European-Non-Finnish population, which is lower than the ClinGen Lysosomal Diseases VCEP threshold (<0.001) for PM2_Supporting, meeting this criterion. There is a ClinVar entry for this variant (Variation ID: 552368). In summary, this variant meets the criteria to be classified as pathogenic for Pompe disease. GAA-specific ACMG/AMP criteria applied, as specified by the ClinGen Lysosomal Diseases VCEP (Specifications Version 2.0): PVS1, PP4, PM2_Supporting, PM3_Supporting.(Classification approved by the ClinGen Lysosomal Diseases VCEP, July 3, 2023) LINK:https://erepo.genome.network/evrepo/ui/classification/CA401325116/MONDO:0009290/010

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: GAA NM_000152.5 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:5
• Conservation: PhyloP100: 5.17

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]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PM3: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GAA	NM_000152.5	c.2407C>T	p.Gln803Ter	stop_gained	17/20	ENST00000302262.8	NP_000143.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GAA	ENST00000302262.8	c.2407C>T	p.Gln803Ter	stop_gained	17/20	1	NM_000152.5	ENSP00000305692	P1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152210 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000483

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: 0.00

Gnomad OTH AF: 0.000478

GnomAD3 exomes AF: 0.00000402 AC: 1 AN: 248496 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135010

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000898

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460416 Hom.: 0 Cov.: 35 AF XY: 0.00000138 AC XY: 1 AN XY: 726516

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152210 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74360

Gnomad4 AFR AF: 0.0000483

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.000478

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: reviewed by expert panel

Submissions by phenotype

Glycogen storage disease, type II Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Sep 18, 2023	- -
Pathogenic, reviewed by expert panel	curation	ClinGen Lysosomal Storage Disorder Variant Curation Expert Panel	Jul 03, 2023	The NM_000152.5:c.2407C>T (p.Gln803Ter) variant in GAA is a nonsense variant predicted to cause a premature stop codon in biologically-relevant-exon 17 (out of 20 exons), leading to nonsense mediated decay in a gene in which loss-of-function is an established disease mechanism (PVS1). One patient with late onset Pompe disease with this variant and treated by enzyme replacement therapy has been reported (PP4). This individual is compound heterozygous for the variant and "IVS 0-45T>G" (assumed to be c.-32-13T>G), a pathogenic variant in GAA, phase unknown (PMID: 26572913) (PM3_Supporting). Two additional patients have been reported to be compound heterozygous for p.Gln803Ter but the cDNA change provided is incorrect and thus this data was not included (PMID: 21940687). The highest population minor allele frequency in gnomAD v2.1.1 is 0.00001 (1/111412 alleles) in the European-Non-Finnish population, which is lower than the ClinGen Lysosomal Diseases VCEP threshold (<0.001) for PM2_Supporting, meeting this criterion. There is a ClinVar entry for this variant (Variation ID: 552368). In summary, this variant meets the criteria to be classified as pathogenic for Pompe disease. GAA-specific ACMG/AMP criteria applied, as specified by the ClinGen Lysosomal Diseases VCEP (Specifications Version 2.0): PVS1, PP4, PM2_Supporting, PM3_Supporting. (Classification approved by the ClinGen Lysosomal Diseases VCEP, July 3, 2023) -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jun 20, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 23, 2023	This sequence change creates a premature translational stop signal (p.Gln803*) in the GAA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in GAA are known to be pathogenic (PMID: 18425781, 22252923). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This premature translational stop signal has been observed in individual(s) with Pompe disease (PMID: 26572913). ClinVar contains an entry for this variant (Variation ID: 552368). For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Revvity Omics, Revvity

Oct 19, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.63
CADD	Pathogenic	47
DANN	Uncertain	1.0
Eigen	Pathogenic	0.81
Eigen_PC	Uncertain	0.63
FATHMM_MKL	Pathogenic	0.97	D
MutationTaster	Benign	1.0	A;A
Vest4		0.88
GERP RS		4.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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

Publications

LitVar

Other links and lift over

dbSNP: rs1344266804; hg19: chr17-78091474; COSMIC: COSV56409787; COSMIC: COSV56409787;