rs193922331

Variant names:

• chr7-44147726-A-G
• rs193922331
• NM_000162.5:c.787T>C

Your query was ambiguous. Multiple possible variants found:

• chr7-44147726-A-G
• chr7-44147726-A-T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PP2 PM2_Supporting PP4_Moderate PS4 PP1_Strong

This summary comes from the ClinGen Evidence Repository: The c.787T>C variant in the glucokinase gene, GCK, causes an amino acid change of serine to proline at codon 263 (p.(Ser263Pro)) of NM_000162.5. This variant was identified in at least 14 unrelated individuals with hyperglycemia (PS4; PMID:32074423, internal lab contributors). This variant has a gnomAD v4.1.0 Grpmax filtering allele frequency of 2.80e-7, which is below the threshold for PM2_Supporting (Grpmax FAF <= 0.000003) (PM2_Supporting). This variant segregated with diabetes/hyperglycemia, with at least 21 informative meioses in 9 families (PP1_Strong; PMID:32074423, internal lab contributors). GCK is defined by the ClinGen MDEP as a gene that has a low rate of benign missense variation and has pathogenic missense variants as a common mechanism of disease (PP2). This variant was identified in an individual with a clinical history highly specific for GCK-hyperglycemia (fasting glucose 5.5-8 mmol/L and HbA1c 5.6 - 7.6% and antibody negative) (PP4_Moderate; internal lab contributors). This variant has a REVEL score of 0.689, which is between the ClinGen MDEP thresholds for BP4 and PP3, predicting neither a damaging nor benign impact on GCK function. The relative activity index (RAI) of this variant was above the MDEP cutoff of 0.5, and while the variant appears to result in thermal instability, the relative stability index was not calculated, therefore PS3_Supporting will not be applied (PMID:16731834).In summary, c.787T>C meets the criteria to be classified as pathogenic for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 2.0.0, approved 2/17/2025): PS4, PM2_Supporting, PP1_Strong, PP2, PP4_Moderate. LINK:https://erepo.genome.network/evrepo/ui/classification/CA152961/MONDO:0015967/086

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GCK NM_000162.5 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:11
• Conservation: PhyloP100: 0.326
• Publications: 18 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: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• 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

LOC105375258 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PP1: For more information check the summary or visit ClinGen Evidence Repository.
• PP2: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000162.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GCK	NM_000162.5	MANE Select	c.787T>C	p.Ser263Pro	missense	Exon 7 of 10	NP_000153.1	Q53Y25
	GCK	NM_033507.3		c.790T>C	p.Ser264Pro	missense	Exon 7 of 10	NP_277042.1	P35557-2
	GCK	NM_033508.3		c.784T>C	p.Ser262Pro	missense	Exon 8 of 11	NP_277043.1	P35557-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GCK	ENST00000403799.8	TSL:1 MANE Select	c.787T>C	p.Ser263Pro	missense	Exon 7 of 10	ENSP00000384247.3	P35557-1
	GCK	ENST00000395796.8	TSL:1	n.*785T>C		non_coding_transcript_exon	Exon 8 of 11	ENSP00000379142.4	A0A8C8KJG0
	GCK	ENST00000395796.8	TSL:1	n.*785T>C		3_prime_UTR	Exon 8 of 11	ENSP00000379142.4	A0A8C8KJG0

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152218 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461152 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726904

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: 26132

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52738

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111970

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152218 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74372

African (AFR) AF: 0.00 AC: 0 AN: 41454

American (AMR) AF: 0.00 AC: 0 AN: 15288

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10628

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68026

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00000469 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
3	-	-	not provided (3)
2	-	-	Maturity-onset diabetes of the young (2)
2	-	-	Maturity-onset diabetes of the young type 2 (2)
1	-	-	GCK-related disorder (1)
1	-	-	Gestational diabetes (1)
1	-	-	Monogenic diabetes (1)
1	-	-	Type 2 diabetes mellitus;C0342277:Maturity-onset diabetes of the young type 2 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.60
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.19
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.62	D
Eigen	Benign	-0.45
Eigen_PC	Benign	-0.40
FATHMM_MKL	Benign	0.75	D
LIST_S2	Uncertain	0.92	D
M_CAP	Pathogenic	0.40	D
MetaRNN	Uncertain	0.61	D
MetaSVM	Uncertain	0.58	D
MutationAssessor	Benign	1.5	L
PhyloP100		0.33
PrimateAI	Benign	0.42	T
PROVEAN	Benign	-1.7	N
REVEL	Pathogenic	0.69
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.018	D
Polyphen		0.048	B
Vest4		0.47
MutPred		0.79		Loss of glycosylation at S263 (P = 0.0429)
MVP		0.91
MPC		1.4
ClinPred		0.86	D
GERP RS		-0.043
Varity_R		0.90
gMVP		1.0
Mutation Taster		=2/98	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs193922331; hg19: chr7-44187325;