3-81577973-G-C

Variant names:

• chr3-81577973-G-C
• rs137852888
• NM_000158.4:c.1570C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP3_Moderate PP5

The NM_000158.4(GBE1):​c.1570C>G​(p.Arg524Gly) 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R524Q) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GBE1 NM_000158.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 7.70
• Publications: 12 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: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a helix (size 19) in uniprot entity GLGB_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) in NM_000158.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr3-81577972-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 2782.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.924
• PP5: Variant 3-81577973-G-C is Pathogenic according to our data. Variant chr3-81577973-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 456517.

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GBE1	NM_000158.4	MANE Select	c.1570C>G	p.Arg524Gly	missense	Exon 12 of 16	NP_000149.4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GBE1	ENST00000429644.7	TSL:1 MANE Select	c.1570C>G	p.Arg524Gly	missense	Exon 12 of 16	ENSP00000410833.2
	GBE1	ENST00000895874.1		c.1564C>G	p.Arg522Gly	missense	Exon 12 of 16	ENSP00000565933.1
	GBE1	ENST00000942742.1		c.1564C>G	p.Arg522Gly	missense	Exon 12 of 16	ENSP00000612801.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	-	Glycogen storage disease, type IV;C1849722:Adult polyglucosan body disease (1)
1	-	-	Glycogen storage disease, type IV;C1856301:Glycogen storage disease IV, classic hepatic (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.46
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.86	D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.48	D
MetaRNN	Pathogenic	0.92	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.3	H
PhyloP100		7.7
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-6.5	D
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.93
MutPred		0.71		Gain of helix (P = 0.0128)
MVP		0.97
MPC		0.26
ClinPred		1.0	D
GERP RS		4.9
Varity_R		0.95
gMVP		0.96
Mutation Taster		=4/96	disease causing

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: rs137852888; hg19: chr3-81627124;