rs758882822

Positions:

• chr1-99875413-C-A
• chr1-99875413-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000642.3(AGL):​c.1241C>A​(p.Pro414Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,461,828 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: not found (cov: 33)
  • Exomes 𝑓: 0.000013 (0 hom.)
• Consequence: AGL NM_000642.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 7.51

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.897

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AGL	NM_000642.3	c.1241C>A	p.Pro414Gln	missense_variant	10/34	ENST00000361915.8	NP_000633.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AGL	ENST00000361915.8	c.1241C>A	p.Pro414Gln	missense_variant	10/34	1	NM_000642.3	ENSP00000355106	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251378 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135858

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: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000130 AC: 19 AN: 1461828 Hom.: 0 Cov.: 32 AF XY: 0.0000165 AC XY: 12 AN XY: 727208

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: 0.0000171

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Glycogen storage disease type III Uncertain:4

Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Apr 11, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Jul 01, 2021	- -
Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Jun 29, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Feb 18, 2022	This sequence change replaces proline, which is neutral and non-polar, with glutamine, which is neutral and polar, at codon 414 of the AGL protein (p.Pro414Gln). This variant is present in population databases (rs758882822, 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: 967966). 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: "Probably Damaging"; 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	Pathogenic	0.73
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.22
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.46	T;T;T;T;.
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.97	D;.;.;.;D
M_CAP	Pathogenic	0.37	D
MetaRNN	Pathogenic	0.90	D;D;D;D;D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Pathogenic	3.6	H;H;H;H;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-7.0	D;D;D;D;D
REVEL	Pathogenic	0.81
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D
Polyphen		1.0	D;D;D;D;D
Vest4		0.88
MutPred		0.45		Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);.;
MVP		0.98
MPC		0.29
ClinPred		1.0	D
GERP RS		5.0
Varity_R		0.82
gMVP		0.89

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: rs758882822; hg19: chr1-100340969;