rs766733439

Positions:

chr12-21559170-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1PM2PP3_StrongPP5_Moderate

The NM_021957.4(GYS2):c.1230-1G>A variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000818 in 1,589,064 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: 32)

Exomes 𝑓: 0.0000083 ( 0 hom. )

Consequence

GYS2
NM_021957.4 splice_acceptor

Scores

Splicing: ADA: 1.000

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 7.68

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 5.5, offset of 2, new splice context is: aacattttttccctgcaaAGgag. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.

PM2

Very rare variant in population databases, with high coverage;

PP3

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

PP5

Variant 12-21559170-C-T is Pathogenic according to our data. Variant chr12-21559170-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 402231.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	Effect	MANE
GYS2	NM_021957.4 linkuse as main transcript	c.1230-1G>A	splice_acceptor_variant	ENST00000261195.3
GYS2	XM_006719063.4 linkuse as main transcript	c.999-1G>A	splice_acceptor_variant
GYS2	XM_024448960.2 linkuse as main transcript	c.1230-1G>A	splice_acceptor_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GYS2	ENST00000261195.3 linkuse as main transcript	c.1230-1G>A		splice_acceptor_variant		1	NM_021957.4	P1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151932

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000200

AC:

AN:

250336

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135378

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:

0.0000441

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000835

AC:

AN:

1437132

Hom.:

Cov.:

AF XY:

0.0000126

AC XY:

AN XY:

716462

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:

0.0000110

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000658

AC:

AN:

151932

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74202

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:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000675

Hom.:

Bravo

AF:

0.0000113

ExAC

AF:

0.0000165

AC:

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

Likely pathogenic, criteria provided, single submitter

clinical testing

Knight Diagnostic Laboratories, Oregon Health and Sciences University

Jul 24, 2015

This variant is predicted to affect the splice-acceptor site in intron 9 of the GYS2 gene. The frequency of this variant is very low in the ExAC database and is absent in both the 1000 Genomes and Exome Sequencing Project databases. In addition, splice-site computational algorithms have predicted this variant to abrogate splicing. Loss-of-function mutations are a known mechanism of disease for this disorder; therefore, we have provisionally classified this variant as Likely Pathogenic. We have confirmed this sequence change in our laboratory using Sanger sequencing. However, splicing studies are necessary to confirm this interpretation. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.58

BayesDel_noAF

Pathogenic

0.39

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.96

FATHMM_MKL

Pathogenic

0.99

MutationTaster

Benign

1.0

GERP RS

4.8

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.94

SpliceAI score (max)

0.99

Details are displayed if max score is > 0.2

DS_AG_spliceai

0.87

Position offset: -3

DS_AL_spliceai

0.99

Position offset: -1

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