12-21546416-A-G

Position:

• chr12-21546416-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_021957.4(GYS2):​c.1477T>C​(p.Tyr493His) 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GYS2 NM_021957.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.26

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.946

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GYS2	NM_021957.4	c.1477T>C	p.Tyr493His	missense_variant	12/16	ENST00000261195.3	NP_068776.2
GYS2	XM_024448960.2	c.1477T>C	p.Tyr493His	missense_variant	12/17		XP_024304728.1
GYS2	XM_006719063.4	c.1246T>C	p.Tyr416His	missense_variant	11/15		XP_006719126.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GYS2	ENST00000261195.3	c.1477T>C	p.Tyr493His	missense_variant	12/16	1	NM_021957.4	ENSP00000261195	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 26

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.78	D
Eigen	Pathogenic	0.77
Eigen_PC	Uncertain	0.64
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.096	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Uncertain	0.47	D
MutationAssessor	Pathogenic	3.4	M
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.91	D
PROVEAN	Pathogenic	-4.8	D
REVEL	Pathogenic	0.89
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.89
MutPred		0.79		Gain of disorder (P = 0.0197);
MVP		0.89
MPC		0.62
ClinPred		1.0	D
GERP RS		4.5
Varity_R		0.86
gMVP		0.89

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

Publications

LitVar

Other links and lift over

dbSNP: rs539369206; hg19: chr12-21699350;