16-30756695-A-G

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 4P and 2B. PM1PM2BP4_Moderate

The NM_000294.3(PHKG2):c.907A>G(p.Thr303Ala) variant causes a missense change. The variant allele was found at a frequency of 0.0000031 in 1,612,984 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T303S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

PHKG2
NM_000294.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.58

Publications

0 publications found

Variant links:

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

PHKG2 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM1

In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000294.3

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.123589486).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000294.3. 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.907A>G	p.Thr303Ala	missense	Exon 9 of 10	NP_000285.1
	PHKG2	NM_001172432.2		c.907A>G	p.Thr303Ala	missense	Exon 9 of 11	NP_001165903.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
PHKG2	ENST00000563588.6	TSL:1 MANE Select	c.907A>G	p.Thr303Ala	missense	Exon 9 of 10	ENSP00000455607.1
PHKG2	ENST00000328273.11	TSL:5	c.919A>G	p.Thr307Ala	missense	Exon 9 of 10	ENSP00000329968.7
PHKG2	ENST00000424889.7	TSL:2	c.907A>G	p.Thr303Ala	missense	Exon 9 of 11	ENSP00000388571.3

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151236

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000487

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000399

AC:

AN:

250844

AF XY:

0.00

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:

0.00000882

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461748

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727170

show subpopulations

African (AFR)

AF:

0.0000299

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53278

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00000180

AC:

AN:

1112012

Other (OTH)

AF:

0.00

AC:

AN:

60392

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.458

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000132

AC:

AN:

151236

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

73786

show subpopulations

African (AFR)

AF:

0.0000487

AC:

AN:

41044

American (AMR)

AF:

0.00

AC:

AN:

15198

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5148

South Asian (SAS)

AF:

0.00

AC:

AN:

4790

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10474

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

67816

Other (OTH)

AF:

0.00

AC:

AN:

2070

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.550

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.0000151

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Glycogen storage disease IXc

Uncertain:1

Oct 05, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This sequence change replaces threonine with alanine at codon 303 of the PHKG2 protein (p.Thr303Ala). The threonine residue is highly conserved and there is a small physicochemical difference between threonine and alanine. This variant is present in population databases (rs780358808, ExAC 0.002%). This variant has not been reported in the literature in individuals with PHKG2-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C55").

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.095

BayesDel_addAF

Benign

-0.21

BayesDel_noAF

Benign

-0.54

CADD

Benign

(source)

DANN

Benign

0.92

DEOGEN2

Benign

0.22

Eigen

Benign

-0.20

Eigen_PC

Benign

0.031

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Benign

0.51

M_CAP

Benign

0.0045

MetaRNN

Benign

0.12

MetaSVM

Benign

-1.1

MutationAssessor

Benign

0.20

PhyloP100

5.6

PrimateAI

Uncertain

0.53

PROVEAN

Benign

-0.34

REVEL

Benign

0.034

Sift

Benign

0.32

Sift4G

Benign

0.76

Polyphen

0.0020

Vest4

0.32

MVP

0.51

MPC

0.36

ClinPred

0.13

GERP RS

3.6

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

2.7

Varity_R

0.034

gMVP

0.31

Mutation Taster

=89/11

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over