1-99902707-C-G

Variant names:

• chr1-99902707-C-G
• rs775498547
• NM_000642.3:c.3613C>G

Variant summary

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

The NM_000642.3(AGL):​c.3613C>G​(p.Gln1205Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000404 in 1,461,034 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000040 (0 hom.)
• Consequence: AGL NM_000642.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 7.54

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 rank	MANE	Protein	UniProt
AGL	NM_000642.3	c.3613C>G	p.Gln1205Glu	missense_variant	Exon 27 of 34	ENST00000361915.8	NP_000633.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
AGL	ENST00000361915.8	c.3613C>G	p.Gln1205Glu	missense_variant	Exon 27 of 34	1	NM_000642.3	ENSP00000355106.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000199 AC: 5 AN: 250638 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135628

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000579

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: 0.0000265

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000404 AC: 59 AN: 1461034 Hom.: 0 Cov.: 30 AF XY: 0.0000385 AC XY: 28 AN XY: 726864

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: 0.0000513

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000557 Hom.: 0

Bravo AF: 0.0000189

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.000259 AC: 1

ExAC AF: 0.0000165 AC: 2

EpiCase AF: 0.0000545

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Glycogen storage disease type III Uncertain:2

Apr 11, 2023

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 08, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamine, which is neutral and polar, with glutamic acid, which is acidic and polar, at codon 1205 of the AGL protein (p.Gln1205Glu). This variant is present in population databases (rs775498547, gnomAD 0.006%). 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: 1376413). 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: "Tolerated"; 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. -

Inborn genetic diseases Uncertain:1

Mar 24, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.3613C>G (p.Q1205E) alteration is located in exon 27 (coding exon 26) of the AGL gene. This alteration results from a C to G substitution at nucleotide position 3613, causing the glutamine (Q) at amino acid position 1205 to be replaced by a glutamic acid (E). 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	Benign	0.13
BayesDel_addAF	Benign	-0.025	T
BayesDel_noAF	Benign	-0.10
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.24	T;T;T;T;.
Eigen	Pathogenic	0.73
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;.;.;.;D
M_CAP	Benign	0.036	D
MetaRNN	Uncertain	0.65	D;D;D;D;D
MetaSVM	Benign	-0.38	T
MutationAssessor	Uncertain	2.5	M;M;M;M;.
PrimateAI	Uncertain	0.52	T
PROVEAN	Uncertain	-2.4	N;N;N;N;N
REVEL	Uncertain	0.46
Sift	Uncertain	0.012	D;D;D;D;D
Sift4G	Uncertain	0.023	D;D;D;D;D
Polyphen		0.93	P;P;P;P;P
Vest4		0.56
MutPred		0.73		Gain of ubiquitination at K1210 (P = 0.1191);Gain of ubiquitination at K1210 (P = 0.1191);Gain of ubiquitination at K1210 (P = 0.1191);Gain of ubiquitination at K1210 (P = 0.1191);.;
MVP		0.87
MPC		0.25
ClinPred		0.74	D
GERP RS		6.0
Varity_R		0.38
gMVP		0.82

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: rs775498547; hg19: chr1-100368263; COSMIC: COSV99038330;