rs202084554

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000642.3(AGL):c.622T>C(p.Trp208Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000334 in 1,613,760 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. W208Y) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00035 ( 0 hom. )

Consequence

AGL
NM_000642.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 7.76

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:

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ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.976

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AGL	NM_000642.3 linkuse as main transcript	c.622T>C	p.Trp208Arg	missense_variant	5/34	ENST00000361915.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AGL	ENST00000361915.8 linkuse as main transcript	c.622T>C	p.Trp208Arg	missense_variant	5/34	1	NM_000642.3	P1	P35573-1

Frequencies

GnomAD3 genomes

AF:

0.000197

AC:

AN:

152172

Hom.:

Cov.:

show subpopulations

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:

0.000397

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000677

AC:

AN:

251254

Hom.:

AF XY:

0.0000884

AC XY:

AN XY:

135810

show subpopulations

Gnomad AFR exome

AF:

0.0000616

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:

0.000141

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000348

AC:

509

AN:

1461588

Hom.:

Cov.:

AF XY:

0.000338

AC XY:

246

AN XY:

727106

show subpopulations

Gnomad4 AFR exome

AF:

0.0000598

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:

0.000426

Gnomad4 OTH exome

AF:

0.000547

GnomAD4 genome

AF:

0.000197

AC:

AN:

152172

Hom.:

Cov.:

AF XY:

0.000121

AC XY:

AN XY:

74330

show subpopulations

Gnomad4 AFR

AF:

0.0000724

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:

0.000397

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000189

Hom.:

Bravo

AF:

0.000185

TwinsUK

AF:

0.000539

AC:

ALSPAC

AF:

0.000259

AC:

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.000349

AC:

ExAC

AF:

0.0000659

AC:

EpiCase

AF:

0.000327

EpiControl

AF:

0.000237

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Glycogen storage disease type III

Uncertain:5

Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Aug 04, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Oct 17, 2022	This sequence change replaces tryptophan, which is neutral and slightly polar, with arginine, which is basic and polar, at codon 208 of the AGL protein (p.Trp208Arg). This variant is present in population databases (rs202084554, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with AGL-related conditions. ClinVar contains an entry for this variant (Variation ID: 456512). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt AGL protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jul 15, 2021	- -
Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Oct 28, 2019	- -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 18, 2020

The c.622T>C (p.W208R) alteration is located in exon 5 (coding exon 4) of the AGL gene. This alteration results from a T to C substitution at nucleotide position 622, causing the tryptophan (W) at amino acid position 208 to be replaced by an arginine (R). Based on data from the Genome Aggregation Database (gnomAD) database, the AGL c.622T>C alteration was observed in 0.01% (25/282652) of total alleles studied, with a frequency of 0.02% (23/129016) in the European (non-Finnish) subpopulation. This amino acid position is highly conserved in available vertebrate species. The p.W208R alteration is predicted to be deleterious by in silico analysis. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.94

BayesDel_addAF

Pathogenic

0.21

BayesDel_noAF

Pathogenic

0.37

Cadd

Pathogenic

Dann

Uncertain

1.0

DEOGEN2

Benign

0.33

T;T;T;T;.

Eigen

Pathogenic

0.84

Eigen_PC

Pathogenic

0.79

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.82

T;.;.;.;T

M_CAP

Uncertain

0.16

MetaRNN

Pathogenic

0.98

D;D;D;D;D

MetaSVM

Uncertain

0.59

MutationAssessor

Pathogenic

3.2

M;M;M;M;.

MutationTaster

Benign

1.0

D;D;D;D;D;D;D

PrimateAI

Uncertain

0.70

PROVEAN

Pathogenic

-11

D;D;D;D;D

REVEL

Pathogenic

0.88

Sift

Uncertain

0.0030

D;D;D;D;D

Sift4G

Uncertain

0.012

D;D;D;D;D

Polyphen

1.0

D;D;D;D;D

Vest4

0.90

MutPred

0.63

Gain of disorder (P = 0.0421);Gain of disorder (P = 0.0421);Gain of disorder (P = 0.0421);Gain of disorder (P = 0.0421);.;

MVP

0.96

MPC

0.36

ClinPred

0.99

GERP RS

5.5

Varity_R

0.84

gMVP

0.94

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

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