17-42900923-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PM5 PP3

The NM_000151.4(G6PC1):c.47C>G(p.Thr16Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,888 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T16A) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: G6PC1 NM_000151.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.86

Genes affected

G6PC1 (HGNC:4056): (glucose-6-phosphatase catalytic subunit 1) Glucose-6-phosphatase (G6Pase) is a multi-subunit integral membrane protein of the endoplasmic reticulum that is composed of a catalytic subunit and transporters for G6P, inorganic phosphate, and glucose. This gene (G6PC) is one of the three glucose-6-phosphatase catalytic-subunit-encoding genes in human: G6PC, G6PC2 and G6PC3. Glucose-6-phosphatase catalyzes the hydrolysis of D-glucose 6-phosphate to D-glucose and orthophosphate and is a key enzyme in glucose homeostasis, functioning in gluconeogenesis and glycogenolysis. Mutations in this gene cause glycogen storage disease type I (GSD1). This disease, also known as von Gierke disease, is a metabolic disorder characterized by severe hypoglycemia associated with the accumulation of glycogen and fat in the liver and kidneys.[provided by RefSeq, Feb 2011]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a topological_domain Lumenal (size 27) in uniprot entity G6PC1_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_000151.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.814

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
G6PC1	NM_000151.4	c.47C>G	p.Thr16Arg	missense_variant	1/5	ENST00000253801.7
G6PC1	NM_001270397.2	c.47C>G	p.Thr16Arg	missense_variant	1/5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
G6PC1	ENST00000253801.7	c.47C>G	p.Thr16Arg	missense_variant	1/5	1	NM_000151.4	P1
G6PC1	ENST00000592383.5	c.47C>G	p.Thr16Arg	missense_variant	1/5	2
G6PC1	ENST00000585489.1	c.47C>G	p.Thr16Arg	missense_variant	1/4	5
G6PC1	ENST00000588481.1	n.112C>G		non_coding_transcript_exon_variant	1/2	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461888 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Glycogen storage disease due to glucose-6-phosphatase deficiency type IA Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Counsyl

Oct 18, 2017

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.83
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.34
Cadd	Uncertain	24
Dann	Uncertain	0.99
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.90	D;D;D
M_CAP	Benign	0.058	D
MetaRNN	Pathogenic	0.81	D;D;D
MetaSVM	Uncertain	-0.0074	T
MutationAssessor	Uncertain	2.4	M;M;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.65	T
Sift4G	Uncertain	0.028	D;D;D
Polyphen		1.0	.;D;.
Vest4		0.90
MutPred		0.56		Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);
MVP		0.97
MPC		0.78
ClinPred		0.99	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.54
gMVP		0.94

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: rs1555558914; hg19: chr17-41052940;