rs373804474

chr1-99870489-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000642.3(AGL):c.754A>G(p.Arg252Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,613,968 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 (★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: AGL NM_000642.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 1.56

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.796

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AGL	NM_000642.3	c.754A>G	p.Arg252Gly	missense_variant	6/34	ENST00000361915.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AGL	ENST00000361915.8	c.754A>G	p.Arg252Gly	missense_variant	6/34	1	NM_000642.3	P1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152216 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251328 Hom.: 0 AF XY: 0.0000221 AC XY: 3 AN XY: 135834

Gnomad AFR exome AF: 0.0000615

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: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461752 Hom.: 0 Cov.: 32 AF XY: 0.00000963 AC XY: 7 AN XY: 727184

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: 0.00000899

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152216 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74358

Gnomad4 AFR AF: 0.0000241

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: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000113

ESP6500AA AF: 0.000227 AC: 1

ESP6500EA AF: 0.00 AC: 0

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Glycogen storage disease type III Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Apr 08, 2022	This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 252 of the AGL protein (p.Arg252Gly). This variant is present in population databases (rs373804474, gnomAD 0.004%). 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: 577123). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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, no assertion criteria provided	clinical testing	Natera, Inc.	Oct 28, 2019	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.62
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Pathogenic	0.23
Cadd	Benign	21
Dann	Benign	0.96
DEOGEN2	Benign	0.091	T;T;T;T;.
Eigen	Benign	-0.21
Eigen_PC	Benign	-0.13
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Uncertain	0.95	D;.;.;.;D
M_CAP	Benign	0.070	D
MetaRNN	Pathogenic	0.80	D;D;D;D;D
MetaSVM	Benign	-0.64	T
MutationAssessor	Uncertain	2.4	M;M;M;M;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-2.3	N;N;N;N;N
REVEL	Uncertain	0.57
Sift	Benign	0.42	T;T;T;T;T
Sift4G	Benign	0.37	T;T;T;T;T
Polyphen		0.13	B;B;B;B;B
Vest4		0.94
MVP		0.80
MPC		0.095
ClinPred		0.30	T
GERP RS		2.9
Varity_R		0.27
gMVP		0.92

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: rs373804474; hg19: chr1-100336045;