rs142626724

chr17-80107716-G-Achr17-80107716-G-T

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_000152.5(GAA):c.852G>A(p.Ala284=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0082 in 1,603,506 control chromosomes in the GnomAD database, including 74 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★★).

• Frequency:
  • Genomes: 𝑓 0.0062 (2 hom., cov: 34)
  • Exomes 𝑓: 0.0084 (72 hom.)
• Consequence: GAA NM_000152.5 synonymous
• Clinical Significance: Benign reviewed by expert panel B:13
• Conservation: PhyloP100: -0.377

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 Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.69).
• BP6: Variant 17-80107716-G-A is Benign according to our data. Variant chr17-80107716-G-A is described in ClinVar as [Benign]. Clinvar id is 188477.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr17-80107716-G-A is described in Lovd as [Likely_benign]. Variant chr17-80107716-G-A is described in Lovd as [Benign].
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00624 (893/143118) while in subpopulation NFE AF= 0.01 (647/64660). AF 95% confidence interval is 0.00937. There are 2 homozygotes in gnomad4. There are 404 alleles in male gnomad4 subpopulation. This position pass quality control queck.
• BS2: High Homozygotes in GnomAd at 2 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GAA	NM_000152.5	c.852G>A	p.Ala284=	synonymous_variant	4/20	ENST00000302262.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GAA	ENST00000302262.8	c.852G>A	p.Ala284=	synonymous_variant	4/20	1	NM_000152.5	P1

Frequencies

GnomAD3 genomes AF: 0.00626 AC: 895 AN: 142998 Hom.: 2 Cov.: 34

Gnomad AFR AF: 0.00162

Gnomad AMI AF: 0.00920

Gnomad AMR AF: 0.00595

Gnomad ASJ AF: 0.00927

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00204

Gnomad FIN AF: 0.00266

Gnomad MID AF: 0.0199

Gnomad NFE AF: 0.0100

Gnomad OTH AF: 0.0106

GnomAD3 exomes AF: 0.00629 AC: 1563 AN: 248578 Hom.: 5 AF XY: 0.00650 AC XY: 878 AN XY: 135026

Gnomad AFR exome AF: 0.00137

Gnomad AMR exome AF: 0.00452

Gnomad ASJ exome AF: 0.00602

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00239

Gnomad FIN exome AF: 0.00269

Gnomad NFE exome AF: 0.0103

Gnomad OTH exome AF: 0.00775

GnomAD4 exome AF: 0.00840 AC: 12263 AN: 1460388 Hom.: 72 Cov.: 34 AF XY: 0.00830 AC XY: 6033 AN XY: 726540

Gnomad4 AFR exome AF: 0.00176

Gnomad4 AMR exome AF: 0.00494

Gnomad4 ASJ exome AF: 0.00701

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00237

Gnomad4 FIN exome AF: 0.00308

Gnomad4 NFE exome AF: 0.00972

Gnomad4 OTH exome AF: 0.00824

GnomAD4 genome AF: 0.00624 AC: 893 AN: 143118 Hom.: 2 Cov.: 34 AF XY: 0.00581 AC XY: 404 AN XY: 69592

Gnomad4 AFR AF: 0.00161

Gnomad4 AMR AF: 0.00594

Gnomad4 ASJ AF: 0.00927

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00204

Gnomad4 FIN AF: 0.00266

Gnomad4 NFE AF: 0.0100

Gnomad4 OTH AF: 0.0105

Alfa AF: 0.00767 Hom.: 1

Bravo AF: 0.00629

Asia WGS AF: 0.000866 AC: 3 AN: 3478

EpiCase AF: 0.0136

EpiControl AF: 0.0127

ClinVar

Significance: Benign

Submissions summary: Benign:13

Revision: reviewed by expert panel

Submissions by phenotype

Glycogen storage disease, type II Benign:5

Benign, reviewed by expert panel	curation	ClinGen Lysosomal Storage Disorder Variant Curation Expert Panel	Jan 23, 2020	The highest continental population minor allele frequency for c.852G>A (p.Ala284=) in gnomAD v2.1.1 is 0.01017 in the European non-Finnish population. This is higher than the ClinGen LSD VCEP's BA1 threshold (>0.01), meeting this criterion. There is a ClinVar entry for this variant (Variation ID: 188477, two star review status), with 5 submitters classifying the variant as benign. In summary, this variant meets the criteria to be classified as benign for Pompe disease. GAA-specific ACMG/AMP criteria applied, as specified by the ClinGen LSD VCEP: BA1. -
Likely benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -
Benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jul 08, 2021	- -
Benign, criteria provided, single submitter	clinical testing	Invitae	Feb 01, 2024	- -
Benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Oct 23, 2021	- -

not specified Benign:4

Benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Dec 22, 2015	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Apr 22, 2019	Variant summary: GAA c.852G>A alters a non-conserved nucleotide resulting in a synonymous change. 5/5 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.0063 in 248578 control chromosomes, predominantly at a frequency of 0.01 within the Non-Finnish European subpopulation in the gnomAD database, including 3 homozygotes. The observed variant frequency within Non-Finnish European control individuals in the gnomAD database is approximately 2 fold of the estimated maximal expected allele frequency for a pathogenic variant in GAA causing Glycogen Storage Disease, Type 2 (Pompe Disease) phenotype (0.0042), strongly suggesting that the variant is a benign polymorphism found primarily in populations of Non-Finnish European origin. The variant, c.852G>A has been reported in the literature in individuals affected with Glycogen Storage Disease, Type 2 (Pompe Disease) without strong evidence of causality (Gort_2007, Herzog_2012, Kroos_2008) . These reports do not provide unequivocal conclusions about association of the variant with Glycogen Storage Disease, Type 2 (Pompe Disease). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation and classified the variant as benign. Based on the evidence outlined above, the variant was classified as benign. -
Benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -

not provided Benign:3

Benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Apr 01, 2024	GAA: BP4, BP7, BS1, BS2 -
Likely benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, University Medical Center Utrecht	-	- -
Benign, no assertion criteria provided	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Dec 30, 2016	- -

Cardiovascular phenotype Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 10, 2021

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.69
Cadd	Benign	6.2
Dann	Benign	0.73

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: rs142626724; hg19: chr17-78081515;