1-99884370-G-C

Position:

• chr1-99884370-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_000642.3(AGL):​c.2465G>C​(p.Gly822Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000547 in 1,461,216 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign 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. G822E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: AGL NM_000642.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 3.29

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 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.22454652).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AGL	NM_000642.3	c.2465G>C	p.Gly822Ala	missense_variant	19/34	ENST00000361915.8	NP_000633.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AGL	ENST00000361915.8	c.2465G>C	p.Gly822Ala	missense_variant	19/34	1	NM_000642.3	ENSP00000355106.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000801 AC: 2 AN: 249642 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135432

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: 0.0000177

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461216 Hom.: 0 Cov.: 32 AF XY: 0.00000688 AC XY: 5 AN XY: 726902

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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: 0.00000630

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.00000824 AC: 1

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, no assertion criteria provided	clinical testing	Natera, Inc.	Oct 28, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 13, 2022	This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 822 of the AGL protein (p.Gly822Ala). This variant is present in population databases (rs752820851, gnomAD 0.002%). 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: 526589). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.075
BayesDel_addAF	Benign	-0.11	T
BayesDel_noAF	Benign	-0.38
CADD	Benign	20
DANN	Uncertain	0.98
DEOGEN2	Benign	0.042	T;T;T;T;.
Eigen	Benign	0.024
Eigen_PC	Benign	0.21
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;.;.;.;D
M_CAP	Benign	0.0091	T
MetaRNN	Benign	0.22	T;T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Uncertain	2.2	M;M;M;M;.
PrimateAI	Benign	0.44	T
PROVEAN	Benign	-0.91	N;N;N;N;N
REVEL	Benign	0.082
Sift	Benign	0.31	T;T;T;T;T
Sift4G	Benign	0.54	T;T;T;T;T
Polyphen		0.0030	B;B;B;B;B
Vest4		0.51
MutPred		0.42		Gain of helix (P = 0.005);Gain of helix (P = 0.005);Gain of helix (P = 0.005);Gain of helix (P = 0.005);.;
MVP		0.46
MPC		0.044
ClinPred		0.26	T
GERP RS		5.8
Varity_R		0.28
gMVP		0.51

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs752820851; hg19: chr1-100349926;