rs764539267

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_ModeratePM2PP5_Moderate

The NM_021957.4(GYS2):​c.1229+1G>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000118 in 1,519,086 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

GYS2
NM_021957.4 splice_donor, intron

Scores

5
1
1
Splicing: ADA: 1.000
2

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 7.79

Publications

0 publications found
Variant links:
Genes affected
GYS2 (HGNC:4707): (glycogen synthase 2) The protein encoded by this gene, liver glycogen synthase, catalyzes the rate-limiting step in the synthesis of glycogen - the transfer of a glucose molecule from UDP-glucose to a terminal branch of the glycogen molecule. Mutations in this gene cause glycogen storage disease type 0 (GSD-0) - a rare type of early childhood fasting hypoglycemia with decreased liver glycogen content. [provided by RefSeq, Dec 2009]
GYS2 Gene-Disease associations (from GenCC):
  • glycogen storage disorder due to hepatic glycogen synthase deficiency
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, PanelApp Australia, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.028409092 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 12-21559650-C-T is Pathogenic according to our data. Variant chr12-21559650-C-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 580790.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GYS2NM_021957.4 linkc.1229+1G>A splice_donor_variant, intron_variant Intron 9 of 15 ENST00000261195.3 NP_068776.2 P54840
GYS2XM_024448960.2 linkc.1229+1G>A splice_donor_variant, intron_variant Intron 9 of 16 XP_024304728.1
GYS2XM_006719063.4 linkc.998+1G>A splice_donor_variant, intron_variant Intron 8 of 14 XP_006719126.1
GYS2XM_017019245.3 linkc.*569G>A downstream_gene_variant XP_016874734.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GYS2ENST00000261195.3 linkc.1229+1G>A splice_donor_variant, intron_variant Intron 9 of 15 1 NM_021957.4 ENSP00000261195.2 P54840
ENSG00000285854ENST00000647960.1 linkn.*1231+1G>A splice_donor_variant, intron_variant Intron 16 of 22 ENSP00000497202.1 A0A3B3IS95
ENSG00000285854ENST00000648372.1 linkn.1156+1G>A splice_donor_variant, intron_variant Intron 9 of 10

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152186
Hom.:
0
Cov.:
33
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000797
AC:
2
AN:
250826
AF XY:
0.00000737
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000124
AC:
17
AN:
1366900
Hom.:
0
Cov.:
26
AF XY:
0.0000146
AC XY:
10
AN XY:
685690
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31844
American (AMR)
AF:
0.0000224
AC:
1
AN:
44576
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25540
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39152
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84324
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53346
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5588
European-Non Finnish (NFE)
AF:
0.0000156
AC:
16
AN:
1025236
Other (OTH)
AF:
0.00
AC:
0
AN:
57294
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152186
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74340
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15266
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Glycogen storage disorder due to hepatic glycogen synthase deficiency Pathogenic:1
Aug 30, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change affects a donor splice site in intron 9 of the GYS2 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in GYS2 are known to be pathogenic (PMID: 9691087). This variant is present in population databases (rs764539267, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with GYS2-related conditions. ClinVar contains an entry for this variant (Variation ID: 580790). 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.61
D
BayesDel_noAF
Pathogenic
0.31
CADD
Pathogenic
33
DANN
Uncertain
0.99
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.81
FATHMM_MKL
Pathogenic
0.97
D
PhyloP100
7.8
GERP RS
4.8
Mutation Taster
=1/99
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.93
SpliceAI score (max)
1.0
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.45
Position offset: -3
DS_DL_spliceai
1.0
Position offset: 1

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

Publications

Other links and lift over

dbSNP: rs764539267; hg19: chr12-21712584; API