7-44152421-G-A

Variant names:

• chr7-44152421-G-A
• rs143128547
• NM_000162.5:c.213C>T

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 0P and 10B. BP4_Strong BP6 BP7 BS1

The NM_000162.5(GCK):​c.213C>T​(p.Val71Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000342 in 1,614,156 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.00014 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00036 (0 hom.)
• Consequence: GCK NM_000162.5 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:6
• Conservation: PhyloP100: -1.96
• Publications: 3 publications found

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

ACMG classification

Our verdict: Benign. The variant received -10 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.55).
• BP6: Variant 7-44152421-G-A is Benign according to our data. Variant chr7-44152421-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 447393.
• BP7: Synonymous conserved (PhyloP=-1.96 with no splicing effect.
• BS1: Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000144 (22/152282) while in subpopulation NFE AF = 0.000294 (20/68022). AF 95% confidence interval is 0.000194. There are 0 homozygotes in GnomAd4. There are 5 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GCK	NM_000162.5	c.213C>T	p.Val71Val	synonymous_variant	Exon 3 of 10	ENST00000403799.8	NP_000153.1
GCK	NM_033507.3	c.216C>T	p.Val72Val	synonymous_variant	Exon 3 of 10		NP_277042.1
GCK	NM_033508.3	c.210C>T	p.Val70Val	synonymous_variant	Exon 4 of 11		NP_277043.1
GCK	NM_001354800.1	c.213C>T	p.Val71Val	synonymous_variant	Exon 3 of 11		NP_001341729.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GCK	ENST00000403799.8	c.213C>T	p.Val71Val	synonymous_variant	Exon 3 of 10	1	NM_000162.5	ENSP00000384247.3

Frequencies

GnomAD3 genomes AF: 0.000145 AC: 22 AN: 152164 Hom.: 0 Cov.: 33

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: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.000239 AC: 60 AN: 251348 AF XY: 0.000235

Gnomad AFR exome AF: 0.0000616

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: 0.000493

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.000363 AC: 530 AN: 1461874 Hom.: 0 Cov.: 32 AF XY: 0.000373 AC XY: 271 AN XY: 727242

African (AFR) AF: 0.00 AC: 0 AN: 33478

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

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000464 AC: 4 AN: 86258

European-Finnish (FIN) AF: 0.0000374 AC: 2 AN: 53412

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5768

European-Non Finnish (NFE) AF: 0.000458 AC: 509 AN: 1112002

Other (OTH) AF: 0.000232 AC: 14 AN: 60396

GnomAD4 genome AF: 0.000144 AC: 22 AN: 152282 Hom.: 0 Cov.: 33 AF XY: 0.0000671 AC XY: 5 AN XY: 74470

African (AFR) AF: 0.0000241 AC: 1 AN: 41548

American (AMR) AF: 0.00 AC: 0 AN: 15296

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5178

South Asian (SAS) AF: 0.000207 AC: 1 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.000294 AC: 20 AN: 68022

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.000196 Hom.: 0

Bravo AF: 0.000144

EpiCase AF: 0.000218

EpiControl AF: 0.000356

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:6

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Maturity onset diabetes mellitus in young Benign:2

-

Clinical Genomics, Uppaluri K&H Personalized Medicine Clinic

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: research

Potent mutations in GCK gene is associated with poor secretion of insulin. Its associated with milder forms of diabetes, which can be controlled by diet . However, there is no sufficient evidence to ascertain the significance of rs143128547 in MODY, yet. -

Jun 06, 2019

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Transient Neonatal Diabetes, Recessive Uncertain:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Permanent neonatal diabetes mellitus Uncertain:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

not specified Benign:1

Feb 14, 2024

Athena Diagnostics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Maturity-onset diabetes of the young type 2 Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

not provided Benign:1

May 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hyperinsulinism due to glucokinase deficiency Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.55
CADD	Benign	3.5
DANN	Benign	0.66
PhyloP100		-2.0
Mutation Taster		=100/0	polymorphism

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

Other links and lift over

dbSNP: rs143128547; hg19: chr7-44192020;