rs370792293

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2PP3PP5_Very_Strong

The NM_000642.3(AGL):c.664+3A>G variant causes a splice donor region, intron change. The variant allele was found at a frequency of 0.00000807 in 1,611,320 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

AGL
NM_000642.3 splice_donor_region, intron

Scores

Splicing: ADA: 0.9992

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 4.21

Variant links:

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]

AGL links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 11 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

PP5

Variant 1-99864592-A-G is Pathogenic according to our data. Variant chr1-99864592-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 188994.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AGL	NM_000642.3 linkuse as main transcript	c.664+3A>G		splice_donor_region_variant, intron_variant		ENST00000361915.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AGL	ENST00000361915.8 linkuse as main transcript	c.664+3A>G		splice_donor_region_variant, intron_variant		1	NM_000642.3	P1	P35573-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152230

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000159

AC:

AN:

250976

Hom.:

AF XY:

0.00000737

AC XY:

AN XY:

135702

show subpopulations

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:

0.0000265

Gnomad OTH exome

AF:

0.000164

GnomAD4 exome

AF:

0.00000754

AC:

AN:

1459090

Hom.:

Cov.:

AF XY:

0.00000551

AC XY:

AN XY:

726094

show subpopulations

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:

0.00000901

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152230

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74378

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000473

Hom.:

Bravo

AF:

0.0000189

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Glycogen storage disease type III

Pathogenic:7

Likely pathogenic, no assertion criteria provided	research	Division of Human Genetics, Children's Hospital of Philadelphia	Oct 31, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Genomic Research Center, Shahid Beheshti University of Medical Sciences	Nov 26, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Sep 09, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 24, 2024	This sequence change falls in intron 5 of the AGL gene. It does not directly change the encoded amino acid sequence of the AGL protein. RNA analysis indicates that this variant induces altered splicing and likely results in a shortened protein product. This variant is present in population databases (rs370792293, gnomAD 0.002%). This variant has been observed in individual(s) with glycogen storage disease type III (PMID: 12442284, 16705713, 21691223). This variant is also known as IVS6 +3 A>G. ClinVar contains an entry for this variant (Variation ID: 188994). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this variant results in skipping of exon 5 (also known as exon 6), but is expected to preserve the integrity of the reading-frame (PMID: 12442284). For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jul 15, 2021	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Likely pathogenic, criteria provided, single submitter	literature only	Counsyl	Sep 30, 2014	- -

Glycogen storage disease IIIa

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Apr 21, 2017

Variant summary: The AGL c.664+3A>G variant is an intronic change that involves a conserved nucleotide. 3/5 splice prediction tools predict an impact on normal splicing, which was confirmed by Lucchiar_2002. The cDNA analysis revealed found an in-frame deletion of exon 6 caused by the variant of interest, and, as confirmation, all homozygous patients showed no enzymatic residual activity. This variant was found in 2/120192 control chromosomes at a frequency of 0.0000166, which does not exceed the estimated maximal expected allele frequency of a pathogenic AGL variant (0.0022822). The variant was identified in multiple GSD III patients homozygously or in compound heterozygosity. Lastly, a clinical diagnostic laboratory classifies the variant as "likely pathogenic." Taking together, the variant of interest has been classified as "pathogenic." -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.20

Cadd

Benign

Dann

Uncertain

0.97

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.93

SpliceAI score (max)

0.35

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.35

Position offset: -3

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over