chr3-81537080-T-C

Variant names:

• chr3-81537080-T-C
• rs137852889
• NM_000158.4:c.1634A>G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PP3_Strong PP5_Moderate

The NM_000158.4(GBE1):​c.1634A>G​(p.His545Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. H545H) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GBE1 NM_000158.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:3
• Conservation: PhyloP100: 7.61
• Publications: 7 publications found

Genes affected

GBE1 (HGNC:4180): (1,4-alpha-glucan branching enzyme 1) The protein encoded by this gene is a glycogen branching enzyme that catalyzes the transfer of alpha-1,4-linked glucosyl units from the outer end of a glycogen chain to an alpha-1,6 position on the same or a neighboring glycogen chain. Branching of the chains is essential to increase the solubility of the glycogen molecule and, consequently, in reducing the osmotic pressure within cells. Highest level of this enzyme are found in liver and muscle. Mutations in this gene are associated with glycogen storage disease IV (also known as Andersen's disease). [provided by RefSeq, Jul 2008]

GBE1 Gene-Disease associations (from GenCC):

• glycogen storage disease due to glycogen branching enzyme deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Laboratory for Molecular Medicine, Ambry Genetics, G2P, ClinGen
• adult polyglucosan body disease

  Inheritance: AR Classification: MODERATE, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_000158.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.968
• PP5: Variant 3-81537080-T-C is Pathogenic according to our data. Variant chr3-81537080-T-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2785.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000158.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GBE1	NM_000158.4	MANE Select	c.1634A>G	p.His545Arg	missense	Exon 13 of 16	NP_000149.4

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GBE1	ENST00000429644.7	TSL:1 MANE Select	c.1634A>G	p.His545Arg	missense	Exon 13 of 16	ENSP00000410833.2
	GBE1	ENST00000489715.1	TSL:2	c.1511A>G	p.His504Arg	missense	Exon 13 of 16	ENSP00000419638.1
	GBE1	ENST00000484687.1	TSL:2	n.35A>G		non_coding_transcript_exon	Exon 2 of 3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, single submitter

Submissions by phenotype

Glycogen storage disease, type IV Pathogenic:1

Apr 02, 2009

GeneReviews

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: curation

Glycogen storage disease due to glycogen branching enzyme deficiency, fatal perinatal neuromuscular form Pathogenic:1

Sep 28, 2004

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

Glycogen storage disease, type IV;C1856301:Glycogen storage disease IV, classic hepatic Pathogenic:1

Jan 29, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 545 of the GBE1 protein (p.His545Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with glycogen storage disease (PMID: 15452297). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 2785). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt GBE1 protein function with a positive predictive value of 95%. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.72	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.49	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.9	H
PhyloP100		7.6
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-7.9	D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.86		Gain of sheet (P = 0.1208)
MVP		0.98
MPC		0.26
ClinPred		1.0	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.95
gMVP		0.96
Mutation Taster		=6/94	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs137852889; hg19: chr3-81586231;