16-30751140-C-T

Variant names:

• chr16-30751140-C-T
• rs137853590
• NM_000294.3:c.130C>T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The ENST00000563588.6(PHKG2):​c.130C>T​(p.Arg44*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000479 in 1,461,604 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: PHKG2 ENST00000563588.6 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 4.07
• Publications: 7 publications found

Genes affected

PHKG2 (HGNC:8931): (phosphorylase kinase catalytic subunit gamma 2) Phosphorylase kinase is a polymer of 16 subunits, four each of alpha, beta, gamma and delta. The alpha subunit includes the skeletal muscle and hepatic isoforms, encoded by two different genes. The beta subunit is the same in both the muscle and hepatic isoforms, and encoded by one gene. The gamma subunit also includes the skeletal muscle and hepatic isoforms, and the hepatic isoform is encoded by this gene. The delta subunit is a calmodulin and can be encoded by three different genes. The gamma subunits contain the active site of the enzyme, whereas the alpha and beta subunits have regulatory functions controlled by phosphorylation. The delta subunit mediates the dependence of the enzyme on calcium concentration. Mutations in this gene cause glycogen storage disease type 9C, also known as autosomal liver glycogenosis. Alternatively spliced transcript variants encoding different isoforms have been identified in this gene.[provided by RefSeq, Feb 2010]

PHKG2 Gene-Disease associations (from GenCC):

• glycogen storage disease IXc

  Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp, PanelApp Australia, Labcorp Genetics (formerly Invitae)
• glycogen storage disease due to liver phosphorylase kinase deficiency

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000260899 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 16-30751140-C-T is Pathogenic according to our data. Variant chr16-30751140-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 13628.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: ENST00000563588.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PHKG2	NM_000294.3	MANE Select	c.130C>T	p.Arg44*	stop_gained	Exon 3 of 10	NP_000285.1
	PHKG2	NM_001172432.2		c.130C>T	p.Arg44*	stop_gained	Exon 3 of 11	NP_001165903.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PHKG2	ENST00000563588.6	TSL:1 MANE Select	c.130C>T	p.Arg44*	stop_gained	Exon 3 of 10	ENSP00000455607.1
	PHKG2	ENST00000569762.1	TSL:1	n.107C>T		non_coding_transcript_exon	Exon 2 of 2
	PHKG2	ENST00000328273.11	TSL:5	c.130C>T	p.Arg44*	stop_gained	Exon 3 of 10	ENSP00000329968.7

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251276 AF XY: 0.00

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461604 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 727118

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53144

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000540 AC: 6 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	Glycogen storage disease IXc (3)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	41
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Uncertain	0.94	D
PhyloP100		4.1
Vest4		0.32
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=2/198	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs137853590; hg19: chr16-30762461; COSMIC: COSV60313760; COSMIC: COSV60313760;