rs113994128

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000642.3(AGL):c.1222C>T(p.Arg408Ter) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000285 in 1,613,964 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

AGL
NM_000642.3 stop_gained

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:8O:1

Conservation

PhyloP100: 3.73

Variant links:

Genes affected

AGL (HGNC:321): (amylo-alpha-1, 6-glucosidase, 4-alpha-glucanotransferase) This gene encodes the glycogen debrancher enzyme which is involved in glycogen degradation. This enzyme has two independent catalytic activities which occur at different sites on the protein: a 4-alpha-glucotransferase activity and a amylo-1,6-glucosidase activity. Mutations in this gene are associated with glycogen storage disease although a wide range of enzymatic and clinical variability occurs which may be due to tissue-specific alternative splicing. Alternatively spliced transcripts encoding different isoforms have been described. [provided by RefSeq, Jul 2008]

AGL links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 1-99875394-C-T is Pathogenic according to our data. Variant chr1-99875394-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 1106.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AGL	NM_000642.3 linkuse as main transcript	c.1222C>T	p.Arg408Ter	stop_gained	10/34	ENST00000361915.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AGL	ENST00000361915.8 linkuse as main transcript	c.1222C>T	p.Arg408Ter	stop_gained	10/34	1	NM_000642.3	P1	P35573-1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152138

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000159

AC:

AN:

251310

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135828

show subpopulations

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:

0.0000352

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000294

AC:

AN:

1461826

Hom.:

Cov.:

AF XY:

0.0000303

AC XY:

AN XY:

727208

show subpopulations

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:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000360

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152138

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74326

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000381

Hom.:

Bravo

AF:

0.0000340

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:8Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Glycogen storage disease type III

Pathogenic:5Other:1

Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Dec 20, 2022	- -
not provided, no classification provided	literature only	GeneReviews	-	Founder variant in Faroe Islanders -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Sep 23, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jul 15, 2021	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 15, 2024	This sequence change creates a premature translational stop signal (p.Arg408*) in the AGL gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in AGL are known to be pathogenic (PMID: 19299494). This variant is present in population databases (rs113994128, gnomAD 0.004%). This premature translational stop signal has been observed in individual(s) with glycogen storage disease (PMID: 11378828, 15542399, 23430490). It is commonly reported in individuals of Faroe islands ancestry (PMID: 11378828, 15542399, 23430490). ClinVar contains an entry for this variant (Variation ID: 1106). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Glycogen storage disease IIIa

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Sep 23, 2019	Variant summary: AGL c.1222C>T (p.Arg408X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 1.6e-05 in 251310 control chromosomes (gnomAD). c.1222C>T has been reported in the literature as a founder mutation in the Faroe Islands, but was also found in individuals of different origin who were affected with Glycogen Storage Disease Type IIIa (Santer_2001, Sentner_2012). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, no assertion criteria provided	literature only	OMIM	May 01, 2001	- -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Feb 09, 2021

Not observed at a significant frequency in large population cohorts (Lek et al., 2016); Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 11378828, 25525159, 31661040, 33763395, 23430490, 15542399, 26885414, 20301788, 32374048, 32623374, 33448466, 31028654, 26984562) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.55

BayesDel_noAF

Pathogenic

0.65

Cadd

Pathogenic

Dann

Uncertain

1.0

Eigen

Pathogenic

0.88

Eigen_PC

Pathogenic

0.78

FATHMM_MKL

Uncertain

0.95

MutationTaster

Benign

1.0

A;A;A;A;A;A;A

Vest4

0.96

GERP RS

5.8

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.46

Details are displayed if max score is > 0.2

DS_AL_spliceai

0.46

Position offset: -36

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over