rs143137713

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 8P and 5B. PP5_Very_StrongBS1_SupportingBS2

The NM_004130.4(GYG1):​c.304G>C​(p.Asp102His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00183 in 1,613,688 control chromosomes in the GnomAD database, including 2 homozygotes. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.0011 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0019 ( 2 hom. )

Consequence

GYG1
NM_004130.4 missense

Scores

16
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:15U:3

Conservation

PhyloP100: 9.57

Publications

17 publications found
Variant links:
Genes affected
GYG1 (HGNC:4699): (glycogenin 1) This gene encodes a member of the glycogenin family. Glycogenin is a glycosyltransferase that catalyzes the formation of a short glucose polymer from uridine diphosphate glucose in an autoglucosylation reaction. This reaction is followed by elongation and branching of the polymer, catalyzed by glycogen synthase and branching enzyme, to form glycogen. This gene is expressed in muscle and other tissues. Mutations in this gene result in glycogen storage disease XV. This gene has pseudogenes on chromosomes 1, 8 and 13 respectively. Alternatively spliced transcript variants encoding different isoforms have been identified.[provided by RefSeq, Sep 2010]
GYG1 Gene-Disease associations (from GenCC):
  • polyglucosan body myopathy type 2
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, PanelApp Australia, ClinGen
  • glycogen storage disease XV
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Orphanet, Labcorp Genetics (formerly Invitae), Genomics England PanelApp

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PP5
Variant 3-148996462-G-C is Pathogenic according to our data. Variant chr3-148996462-G-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 162663.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.00106 (161/152300) while in subpopulation AMR AF = 0.00203 (31/15296). AF 95% confidence interval is 0.00147. There are 0 homozygotes in GnomAd4. There are 74 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GYG1NM_004130.4 linkc.304G>C p.Asp102His missense_variant Exon 3 of 8 ENST00000345003.9 NP_004121.2
GYG1NM_001184720.2 linkc.304G>C p.Asp102His missense_variant Exon 3 of 7 NP_001171649.1
GYG1NM_001184721.2 linkc.304G>C p.Asp102His missense_variant Exon 3 of 6 NP_001171650.1
GYG1XM_017006275.2 linkc.127G>C p.Asp43His missense_variant Exon 2 of 6 XP_016861764.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GYG1ENST00000345003.9 linkc.304G>C p.Asp102His missense_variant Exon 3 of 8 1 NM_004130.4 ENSP00000340736.4

Frequencies

GnomAD3 genomes
AF:
0.00106
AC:
161
AN:
152182
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000265
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00203
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00316
Gnomad NFE
AF:
0.00171
Gnomad OTH
AF:
0.000956
GnomAD2 exomes
AF:
0.00102
AC:
257
AN:
251340
AF XY:
0.00101
show subpopulations
Gnomad AFR exome
AF:
0.000246
Gnomad AMR exome
AF:
0.00121
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000464
Gnomad NFE exome
AF:
0.00181
Gnomad OTH exome
AF:
0.000651
GnomAD4 exome
AF:
0.00191
AC:
2787
AN:
1461388
Hom.:
2
Cov.:
31
AF XY:
0.00188
AC XY:
1368
AN XY:
727058
show subpopulations
African (AFR)
AF:
0.000329
AC:
11
AN:
33468
American (AMR)
AF:
0.00130
AC:
58
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.0000938
AC:
5
AN:
53278
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5754
European-Non Finnish (NFE)
AF:
0.00237
AC:
2634
AN:
1111704
Other (OTH)
AF:
0.00131
AC:
79
AN:
60378
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.468
Heterozygous variant carriers
0
131
261
392
522
653
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
108
216
324
432
540
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00106
AC:
161
AN:
152300
Hom.:
0
Cov.:
32
AF XY:
0.000994
AC XY:
74
AN XY:
74478
show subpopulations
African (AFR)
AF:
0.000265
AC:
11
AN:
41554
American (AMR)
AF:
0.00203
AC:
31
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00340
AC:
1
AN:
294
European-Non Finnish (NFE)
AF:
0.00171
AC:
116
AN:
68026
Other (OTH)
AF:
0.000946
AC:
2
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.514
Heterozygous variant carriers
0
9
18
28
37
46
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00154
Hom.:
0
Bravo
AF:
0.00118
TwinsUK
AF:
0.00270
AC:
10
ALSPAC
AF:
0.00337
AC:
13
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00186
AC:
16
ExAC
AF:
0.000914
AC:
111
EpiCase
AF:
0.00207
EpiControl
AF:
0.00202

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:15Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:4Uncertain:2
Jun 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

GYG1: PM3:Strong, PM2:Supporting, PP3 -

Apr 21, 2023
Mayo Clinic Laboratories, Mayo Clinic
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PP3, PP4, PM3, PS4_moderate -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Uncertain significance
Review Status:flagged submission
Collection Method:clinical testing

- -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Uncertain significance
Review Status:flagged submission
Collection Method:clinical testing

- -

Sep 23, 2022
Revvity Omics, Revvity
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 27, 2025
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 29422440, 34662886, 25272951, 27718144, 25741868, 31980526, 34426522, 31589614, 32528171, 31791869, 32477874) -

Polyglucosan body myopathy type 2 Pathogenic:5
Jan 25, 2022
MGZ Medical Genetics Center
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 01, 2014
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Mar 23, 2022
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 01, 2016
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was classified as: Pathogenic. The following ACMG criteria were applied in classifying this variant: PM2,PM3,PS1,PP3,PP4. -

Sep 26, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: GYG1 c.304G>C (p.Asp102His) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.001 in 251340 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in GYG1 causing Polyglucosan Body Myopathy Type 2, allowing no conclusion about variant significance. c.304G>C has been reported in the literature as a biallelic homozygous or compound heterozygous genotype in multiple individuals affected with features of Polyglucosan Body Myopathy Type 2 (Malfatti_2014, Hedber-Oldfors_2017, Topf_2020). These data indicate that the variant is likely to be associated with disease. To our knowledge, no quantifiable variant specific experimental evidence demonstrating an impact on protein function has been reported. Although one study reported that an assay of autoglucosylation in vitro did not show any gel shift after the addition of UDP glucose, suggesting nonfunctional glycogenin-1 (Malfatti_2014). The following publications have been ascertained in the context of this evaluation (PMID: 32528171, 27718144, 25272951). ClinVar contains an entry for this variant (Variation ID: 162663). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Glycogen storage disease XV;C4015452:Polyglucosan body myopathy type 2 Pathogenic:2
Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with histidine, which is basic and polar, at codon 102 of the GYG1 protein (p.Asp102His). This variant is present in population databases (rs143137713, gnomAD 0.2%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individuals with clinical features of glycogenin 1 deficiency (PMID: 25272951, 27718144, 31791869, 32477874). ClinVar contains an entry for this variant (Variation ID: 162663). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt GYG1 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects GYG1 function (PMID: 25272951, 27718144). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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. -

Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Glycogen storage disease XV Pathogenic:2
Mar 23, 2022
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 17, 2023
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a reported mechanism of disease in this gene and is associated with polyglucosan body myopathy 2 (MIM#616199) and glycogen storage disease XV (MIM#613507). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0115 - Variants in this gene are known to have variable expressivity. With multiple cases reporting abnormal glycogen storage, and varying muscular phenotypes, age of onset, and sometimes severe cardiac disorders (PMID: 31791869, PMID: 32477874). (I) 0200 - Variant is predicted to result in a missense amino acid change from aspartic acid to histidine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (290 heterozygotes, 0 homozygotes). (SP) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0600 - Variant is located in the annotated glycosyl transferase family 8 domain (DECIPHER). (I) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been identified in at least six unrelated affected individuals (ClinVar, PMID:25272951, PMID:27718144, PMID: 31791869, PMID: 32477874). It has also been reported as a VUS in ClinVar, including one as a VUS favouring pathogenic and two without further information provided. (SP) 0906 - Segregation evidence for this variant is inconclusive. A homozygous sibling of an affected individual showed no clinical symptoms at 53 years of age (PMID:27718144). (I) 1001 - This variant has strong functional evidence supporting abnormal protein function. Functional studies from a homozygous individual demonstrated protein activity was abolished in cardiac muscle. (PMID:27718144). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Glycogen storage disease Pathogenic:1
May 02, 2024
Molecular Genetics, Royal Melbourne Hospital
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change in GYG1 is predicted to replace aspartic acid with histidine at codon 102, p.(Asp102His). The aspartic acid residue is highly conserved (100 vertebrates, UCSC), and is located in located in the highly conserved DxD motif, which is defined as a critical functional domain (PMID: 27718144). There is a moderate physicochemical difference between aspartic acid and histidine. The highest population minor allele frequency in the population database gnomAD v4.0 is 0.2% (2,750/1,179,730 alleles, 2 homozygotes) in the European (non-Finnish) population. This variant has been detected in at least six individuals with muscle glycogenin 1 deficiency. Of those individuals, three individuals were homozygous presenting with cardiomyopathy and three were compound heterozygous with a second pathogenic variant presenting with neuromuscular features (PMID: 25272951, 27718144, 31791869, 32477874). At least one patient with this variant displayed defective glycogenin-1 function in muscle biopsies after alpha-amylase treatment, which is highly specific for muscle glycogenin 1 deficiency (PMID: 27718144, 31791869). An in vitro functional assay with limited validation demonstrated the variant altered the autoglycosylation function of the protein (PMID: 27718144). Computational evidence predicts a deleterious effect for the missense substitution (REVEL = 0.942). Based on the classification scheme RMH Modified ACMG/AMP Guidelines v1.6.1, this variant is classified as PATHOGENIC. Following criteria are met: PM3_Strong, PM1, PP3_Moderate, PP4, PS3_Supporting. -

GYG1-related disorder Pathogenic:1
Aug 24, 2023
PreventionGenetics, part of Exact Sciences
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The GYG1 c.304G>C variant is predicted to result in the amino acid substitution p.Asp102His. This variant has been previously reported in the compound heterozygous state with a protein truncating variant in two different patients with polyglucosan body myopathy (Malfatti et al. 2014. PubMed ID: 25272951; Lefeuvre et al. 2020. PubMed ID: 32477874). The same variant was also found in the homozygous state via exome sequencing in three unrelated individuals who presented with cardiomyopathy (Hedberg-Oldfors et al. 2017. PubMed ID: 27718144). In all of these studies, morphological analysis revealed accumulation of glycogen and/or polyglucosan bodies in either skeletal or cardiac muscle. Furthermore, in vitro studies showed that the p.Asp102His change lead to the loss of GYG1 autoglucosylation, which would result in a non-functional GYG1 protein (Malfatti et al. 2014. PubMed ID: 25272951; Hedberg-Oldfors et al. 2017. PubMed ID: 27718144). This variant is reported in 0.18% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/3-148714249-G-C). This variant is interpreted as pathogenic. -

not specified Uncertain:1
May 30, 2019
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:flagged submission
Collection Method:clinical testing

Variant classified as Uncertain Significance - Favor Pathogenic. The p.Asp102His variant in GYG1 has been reported in the compound heterozygous state in 1 individual with polyglucosan body myopathy and in the homozygous state in 3 individuals with cardiomyopathy and no muscle weakness but with abnormal glycogen storage as indicated by an endomyocardial biopsy (Malfatti 2014, Hedberg-Oldfors 2017). An in vitro functional study suggests that the p.Asp102His could cause defects in auto-glycosylation upon addition of UPD glucose, however, these types of assays may not accurately represent biological function (Malfatti 2014). This variant has also been reported by other clinical laboratories in ClinVar (Variation ID 162663) and has been identified in 0.18% (235/129154) of European chromosomes by gnomAD (http://gnomad.broadinstitute.org). Computational prediction tools and conservation analyses suggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In summary, while there is some suspicion for a pathogenic role, the clinical significance of this variant is uncertain. ACMG/AMP criteria applied: PM3, PP3, PS3_Supporting, BS1_Supporting. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Pathogenic
0.53
CADD
Pathogenic
33
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.87
D;.;.;.;.;.;D;.
Eigen
Pathogenic
1.2
Eigen_PC
Pathogenic
1.1
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
D;D;D;.;D;D;D;D
M_CAP
Pathogenic
0.58
D
MetaRNN
Uncertain
0.61
D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.3
H;.;H;.;H;.;.;.
PhyloP100
9.6
PrimateAI
Pathogenic
0.90
D
PROVEAN
Pathogenic
-6.8
D;.;D;D;D;D;D;D
REVEL
Pathogenic
0.94
Sift
Pathogenic
0.0
D;.;D;D;D;D;D;D
Sift4G
Pathogenic
0.0
D;D;D;D;D;D;D;D
Polyphen
1.0
D;D;D;D;.;.;.;.
Vest4
0.99
MVP
1.0
MPC
0.56
ClinPred
0.89
D
GERP RS
6.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.98
gMVP
0.88
Mutation Taster
=0/100
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.14
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs143137713; hg19: chr3-148714249; COSMIC: COSV56049205; COSMIC: COSV56049205; API