rs78337075

Positions:

• chr12-21540518-C-T

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 2P and 15B. PM2 BP4_Moderate BP6_Very_Strong BP7 BS1

The NM_021957.4(GYS2):​c.1701G>A​(p.Leu567Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000169 in 1,613,910 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00087 (0 hom., cov: 31)
  • Exomes 𝑓: 0.000096 (1 hom.)
• Consequence: GYS2 NM_021957.4 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: 1.69

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]

ENSG00000285854 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -13 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.46).
• BP6: Variant 12-21540518-C-T is Benign according to our data. Variant chr12-21540518-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 261468.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=1.69 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4_exome allele frequency = 0.0000958 (140/1461680) while in subpopulation AFR AF= 0.00382 (128/33474). AF 95% confidence interval is 0.00328. There are 1 homozygotes in gnomad4_exome. There are 68 alleles in male gnomad4_exome subpopulation. Median coverage is 31. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GYS2	NM_021957.4	c.1701G>A	p.Leu567Leu	synonymous_variant	14/16	ENST00000261195.3	NP_068776.2
GYS2	XM_024448960.2	c.1701G>A	p.Leu567Leu	synonymous_variant	14/17		XP_024304728.1
GYS2	XM_006719063.4	c.1470G>A	p.Leu490Leu	synonymous_variant	13/15		XP_006719126.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GYS2	ENST00000261195.3	c.1701G>A	p.Leu567Leu	synonymous_variant	14/16	1	NM_021957.4	ENSP00000261195.2
ENSG00000285854	ENST00000647960.1	n.*1703G>A		non_coding_transcript_exon_variant	21/23			ENSP00000497202.1
ENSG00000285854	ENST00000647960.1	n.*1703G>A		3_prime_UTR_variant	21/23			ENSP00000497202.1
SPX	ENST00000649016.1	n.4001C>T		non_coding_transcript_exon_variant	5/5

Frequencies

GnomAD3 genomes AF: 0.000874 AC: 133 AN: 152112 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00302

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000196

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: 0.00

Gnomad OTH AF: 0.00239

GnomAD3 exomes AF: 0.000227 AC: 57 AN: 251370 Hom.: 0 AF XY: 0.000228 AC XY: 31 AN XY: 135838

Gnomad AFR exome AF: 0.00332

Gnomad AMR exome AF: 0.0000578

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: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.0000958 AC: 140 AN: 1461680 Hom.: 1 Cov.: 31 AF XY: 0.0000935 AC XY: 68 AN XY: 727156

Gnomad4 AFR exome AF: 0.00382

Gnomad4 AMR exome AF: 0.000112

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: 0.00

Gnomad4 OTH exome AF: 0.000116

GnomAD4 genome AF: 0.000874 AC: 133 AN: 152230 Hom.: 0 Cov.: 31 AF XY: 0.000833 AC XY: 62 AN XY: 74412

Gnomad4 AFR AF: 0.00301

Gnomad4 AMR AF: 0.000196

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00237

Alfa AF: 0.000618 Hom.: 0

Bravo AF: 0.00101

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:2

Likely benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -
Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Jan 08, 2018	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Glycogen storage disorder due to hepatic glycogen synthase deficiency Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 12, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.46
CADD	Benign	13
DANN	Benign	0.78

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.13		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: rs78337075; hg19: chr12-21693452;