16-30748395-T-C

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BA1

The ENST00000424889.7(PHKG2):c.-114T>C variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.985 in 199,858 control chromosomes in the GnomAD database, including 96,984 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.98 (73285 hom., cov: 36)
  • Exomes 𝑓: 1.0 (23699 hom.)
• Consequence: PHKG2 ENST00000424889.7 5_prime_UTR
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: -0.171

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]

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.75).
• BP6: Variant 16-30748395-T-C is Benign according to our data. Variant chr16-30748395-T-C is described in ClinVar as [Benign]. Clinvar id is 318927.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BA1: GnomAd4 highest subpopulation (EAS) allele frequency at 95% confidence interval = 0.994 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PHKG2	NM_000294.3			upstream_gene_variant		ENST00000563588.6
PHKG2	NM_001172432.2			upstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PHKG2	ENST00000563588.6			upstream_gene_variant		1	NM_000294.3	P4

Frequencies

GnomAD3 genomes AF: 0.980 AC: 149265 AN: 152246 Hom.: 73229 Cov.: 36

Gnomad AFR AF: 0.930

Gnomad AMI AF: 1.00

Gnomad AMR AF: 0.996

Gnomad ASJ AF: 1.00

Gnomad EAS AF: 1.00

Gnomad SAS AF: 1.00

Gnomad FIN AF: 1.00

Gnomad MID AF: 1.00

Gnomad NFE AF: 1.00

Gnomad OTH AF: 0.989

GnomAD4 exome AF: 0.999 AC: 47446 AN: 47494 Hom.: 23699 Cov.: 0 AF XY: 0.999 AC XY: 24666 AN XY: 24682

Gnomad4 AFR exome AF: 0.945

Gnomad4 AMR exome AF: 0.995

Gnomad4 ASJ exome AF: 1.00

Gnomad4 EAS exome AF: 1.00

Gnomad4 SAS exome AF: 1.00

Gnomad4 FIN exome AF: 1.00

Gnomad4 NFE exome AF: 1.00

Gnomad4 OTH exome AF: 0.997

GnomAD4 genome AF: 0.980 AC: 149380 AN: 152364 Hom.: 73285 Cov.: 36 AF XY: 0.981 AC XY: 73103 AN XY: 74502

Gnomad4 AFR AF: 0.930

Gnomad4 AMR AF: 0.996

Gnomad4 ASJ AF: 1.00

Gnomad4 EAS AF: 1.00

Gnomad4 SAS AF: 1.00

Gnomad4 FIN AF: 1.00

Gnomad4 NFE AF: 1.00

Gnomad4 OTH AF: 0.989

Alfa AF: 0.990 Hom.: 18388

Bravo AF: 0.978

Asia WGS AF: 0.997 AC: 3469 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:1

Benign, criteria provided, single submitter

clinical testing

GeneDx

Jun 29, 2018

- -

Glycogen storage disease IXc Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.75
Cadd	Benign	9.8
Dann	Benign	0.67

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs11863277; hg19: chr16-30759716;