1-99864547-T-C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PP3_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

10
6
3

Clinical Significance

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

Conservation

PhyloP100: 7.76

Publications

4 publications found
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 Gene-Disease associations (from GenCC):
  • glycogen storage disease III
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Ambry Genetics, Laboratory for Molecular Medicine, Myriad Women’s Health, Orphanet, G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.976

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AGLNM_000642.3 linkc.622T>C p.Trp208Arg missense_variant Exon 5 of 34 ENST00000361915.8 NP_000633.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
AGLENST00000361915.8 linkc.622T>C p.Trp208Arg missense_variant Exon 5 of 34 1 NM_000642.3 ENSP00000355106.3

Frequencies

GnomAD3 genomes
AF:
0.000197
AC:
30
AN:
152172
Hom.:
0
Cov.:
33
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
GnomAD2 exomes
AF:
0.0000677
AC:
17
AN:
251254
AF XY:
0.0000884
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 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.:
0
Cov.:
32
AF XY:
0.000338
AC XY:
246
AN XY:
727106
show subpopulations
African (AFR)
AF:
0.0000598
AC:
2
AN:
33460
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39636
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53396
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.000426
AC:
474
AN:
1111860
Other (OTH)
AF:
0.000547
AC:
33
AN:
60376
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
25
50
75
100
125
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
22
44
66
88
110
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000197
AC:
30
AN:
152172
Hom.:
0
Cov.:
33
AF XY:
0.000121
AC XY:
9
AN XY:
74330
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000397
AC:
27
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000214
Hom.:
0
Bravo
AF:
0.000185
TwinsUK
AF:
0.000539
AC:
2
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.0000659
AC:
8
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
Jul 15, 2021
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 17, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

Oct 28, 2019
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Aug 04, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

Inborn genetic diseases Uncertain:1
Nov 18, 2020
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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
D
BayesDel_noAF
Pathogenic
0.37
CADD
Pathogenic
26
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
D
LIST_S2
Benign
0.82
T;.;.;.;T
M_CAP
Uncertain
0.16
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D
MetaSVM
Uncertain
0.59
D
MutationAssessor
Pathogenic
3.2
M;M;M;M;.
PhyloP100
7.8
PrimateAI
Uncertain
0.70
T
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
D
GERP RS
5.5
Varity_R
0.84
gMVP
0.94
Mutation Taster
=16/84
disease causing

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

Other links and lift over

dbSNP: rs202084554; hg19: chr1-100330103; API