rs774124715

Positions:

• chr1-99892514-C-G
• chr1-99892514-C-T

Variant summary

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

The ENST00000361915.8(AGL):​c.3166C>G​(p.Leu1056Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000684 in 1,461,356 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. L1056L) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: AGL ENST00000361915.8 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 1.54

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AGL	NM_000642.3	c.3166C>G	p.Leu1056Val	missense_variant	24/34	ENST00000361915.8	NP_000633.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AGL	ENST00000361915.8	c.3166C>G	p.Leu1056Val	missense_variant	24/34	1	NM_000642.3	ENSP00000355106	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000279 AC: 7 AN: 251182 Hom.: 0 AF XY: 0.0000295 AC XY: 4 AN XY: 135772

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000381

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461356 Hom.: 0 Cov.: 31 AF XY: 0.00000688 AC XY: 5 AN XY: 726976

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000177

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000497

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ExAC AF: 0.0000247 AC: 3

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	Labcorp Genetics (formerly Invitae), Labcorp	Jul 19, 2022	This sequence change replaces leucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1056 of the AGL protein (p.Leu1056Val). This variant is present in population databases (rs774124715, gnomAD 0.04%). 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: 581232). 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: "Possibly 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. -
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	Benign	0.26
BayesDel_addAF	Benign	-0.14	T
BayesDel_noAF	Benign	-0.12
CADD	Benign	20
DANN	Uncertain	1.0
DEOGEN2	Benign	0.36	T;T;T;T;.
Eigen	Uncertain	0.41
Eigen_PC	Uncertain	0.32
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.91	D;.;.;.;D
M_CAP	Uncertain	0.088	D
MetaRNN	Uncertain	0.73	D;D;D;D;D
MetaSVM	Uncertain	0.0063	D
MutationAssessor	Pathogenic	3.5	M;M;M;M;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Benign	0.42	T
PROVEAN	Benign	-2.2	N;N;N;N;N
REVEL	Uncertain	0.61
Sift	Uncertain	0.010	D;D;D;D;D
Sift4G	Uncertain	0.014	D;D;D;D;D
Polyphen		0.97	D;D;D;D;D
Vest4		0.70
MutPred		0.63		Gain of ubiquitination at K1052 (P = 0.1047);Gain of ubiquitination at K1052 (P = 0.1047);Gain of ubiquitination at K1052 (P = 0.1047);Gain of ubiquitination at K1052 (P = 0.1047);.;
MVP		0.77
MPC		0.15
ClinPred		0.71	D
GERP RS		3.3
Varity_R		0.26
gMVP		0.76

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: rs774124715; hg19: chr1-100358070;