NM_000162.5:c.835G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1PM2PP2PP3

The NM_000162.5(GCK):​c.835G>A​(p.Glu279Lys) variant causes a missense change. The variant allele was found at a frequency of 0.0000031 in 1,610,530 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. E279G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

GCK
NM_000162.5 missense

Scores

5
8
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 4.98

Publications

16 publications found
Variant links:
Genes affected
GCK (HGNC:4195): (glucokinase) This gene encodes a member of the hexokinase family of proteins. Hexokinases phosphorylate glucose to produce glucose-6-phosphate, the first step in most glucose metabolism pathways. In contrast to other forms of hexokinase, this enzyme is not inhibited by its product glucose-6-phosphate but remains active while glucose is abundant. The use of multiple promoters and alternative splicing of this gene result in distinct protein isoforms that exhibit tissue-specific expression in the pancreas and liver. In the pancreas, this enzyme plays a role in glucose-stimulated insulin secretion, while in the liver, this enzyme is important in glucose uptake and conversion to glycogen. Mutations in this gene that alter enzyme activity have been associated with multiple types of diabetes and hyperinsulinemic hypoglycemia. [provided by RefSeq, Aug 2017]
GCK Gene-Disease associations (from GenCC):
  • hyperinsulinism due to glucokinase deficiency
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
  • maturity-onset diabetes of the young type 2
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
  • monogenic diabetes
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • diabetes mellitus, noninsulin-dependent
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • permanent neonatal diabetes mellitus 1
    Inheritance: AR Classification: STRONG, MODERATE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • transient neonatal diabetes mellitus
    Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp
  • maturity-onset diabetes of the young
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • permanent neonatal diabetes mellitus
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM1
In a hotspot region, there are 13 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 12 uncertain in NM_000162.5
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 274 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 3.069 (below the threshold of 3.09). Trascript score misZ: 2.7821 (below the threshold of 3.09). GenCC associations: The gene is linked to transient neonatal diabetes mellitus, monogenic diabetes, permanent neonatal diabetes mellitus 1, diabetes mellitus, noninsulin-dependent, maturity-onset diabetes of the young type 2, hyperinsulinism due to glucokinase deficiency, permanent neonatal diabetes mellitus, maturity-onset diabetes of the young.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.809

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GCKNM_000162.5 linkc.835G>A p.Glu279Lys missense_variant Exon 7 of 10 ENST00000403799.8 NP_000153.1 P35557-1Q53Y25

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GCKENST00000403799.8 linkc.835G>A p.Glu279Lys missense_variant Exon 7 of 10 1 NM_000162.5 ENSP00000384247.3 P35557-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152222
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1458308
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
725032
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33452
American (AMR)
AF:
0.00
AC:
0
AN:
44602
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26016
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39644
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86012
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52532
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5752
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1110038
Other (OTH)
AF:
0.00
AC:
0
AN:
60260
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.538
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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:
0.00000657
AC:
1
AN:
152222
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41460
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000364
Hom.:
0
Bravo
AF:
0.0000113
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jun 30, 2020
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

DNA sequence analysis of the GCK gene demonstrated a sequence change, c.835G>A, in exon 7 that results in an amino acid change, p.Glu279Lys. This sequence change does not appear to have been previously described in patients with GCK-related disorders and has been described in the gnomAD database in one individual which corresponds to a population frequency of 0.0032% (dbSNP rs104894005). The p.Glu279Lys change affects a highly conserved amino acid residue located in a hexokinase C-terminal domain of the GCK protein that is known to be functional. The p.Glu279Lys substitution appears to be deleterious using several in-silico pathogenicity prediction tools (SIFT, PolyPhen2, Align GVGD, REVEL). Due to these contrasting evidences and the lack of functional studies, the clinical significance of the p.Glu279Lys change remains unknown at this time. -

not provided Uncertain:1
Jul 12, 2023
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 glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 279 of the GCK protein (p.Glu279Lys). This variant is present in population databases (no rsID available, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with GCK-related conditions. ClinVar contains an entry for this variant (Variation ID: 1338598). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt GCK protein function. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Pathogenic
0.32
D
BayesDel_noAF
Pathogenic
0.22
CADD
Pathogenic
27
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.52
.;D;.;.;.
Eigen
Uncertain
0.29
Eigen_PC
Uncertain
0.40
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.97
D;D;.;D;D
M_CAP
Pathogenic
0.52
D
MetaRNN
Pathogenic
0.81
D;D;D;D;D
MetaSVM
Uncertain
0.75
D
MutationAssessor
Benign
1.4
.;L;.;.;.
PhyloP100
5.0
PrimateAI
Uncertain
0.70
T
PROVEAN
Benign
-1.4
.;N;N;N;N
REVEL
Uncertain
0.64
Sift
Benign
0.24
.;T;T;T;T
Sift4G
Benign
0.40
T;T;T;T;T
Polyphen
0.95
P;D;P;B;.
Vest4
0.56
MutPred
0.64
.;Gain of ubiquitination at E279 (P = 0.0085);.;.;.;
MVP
0.93
MPC
1.9
ClinPred
0.99
D
GERP RS
5.5
Varity_R
0.75
gMVP
0.98
Mutation Taster
=22/78
disease causing

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

Other links and lift over

dbSNP: rs104894005; hg19: chr7-44187277; COSMIC: COSV100357186; COSMIC: COSV100357186; API