All of the five known MODY genes, HNF-4alpha, glucokinase, HNF-1alpha, HNF-1beta, and IPF1, were previously excluded as being the cause of diabetes in these families.
In conclusion, insulin resistance correlates with the deterioration of glucose tolerance and contributes to the hyperglycaemia of glucokinase-deficient diabetes.
It has resulted in great challenges for researchers elucidating the aetiology of diabetes and related features in other organ systems, for clinicians specifying a diagnosis that leads to improved genetic counselling, predicting of clinical course and changes in treatment, and for patients to altered treatment that has lead to coming off insulin and injections with no alternative (Glucokinase mutations), insulin injections being replaced by tablets (e.g. low dose in HNFalpha or high dose in potassium channel defects -Kir6.2 and SUR1) or with tablets in addition to insulin (e.g. metformin in insulin resistant syndromes).
Individuals with islet autoantibody negative youth-onset forms of diabetes should be evaluated for either glucokinase-MODY or transcription factors MODY.
Elucidating the molecular basis of ligand-mediated control over the GCK-GKRP interaction is expected to impact the development and future refinement of therapeutic agents for diabetes and cardiovascular disease, which result from improper GKRP regulation of GCK.
In the absence of a crystal structure for glucokinase, our models help rationalize the potential effects of mutations in diabetes and hypoglycemia, and the models may also facilitate the discovery of pharmacological glucokinase activators and inhibitors.
Systematic clinical and biochemical characterization and GCK mutational analysis were implemented to determine the diabetes etiology in five relatives.
Because pharmacological glucokinase activators are evaluated for the treatment of diabetes, the aim of the study was to assess if these polymorphisms could provide evidence for an increased cardiovascular risk of long-term glucokinase activation.
Surprisingly, extracts from liver of diabetic GCK mutants inhibited activity of the recombinant enzyme, a property that was also observed in liver extracts from mice with streptozotocin-induced diabetes.
The glucokinase and mitochondrial tRNA(Leu(UUR)) genes were screened for mutations in at least one affected subject from each family in order to assess the contribution of mutations in these genes to the development of the diabetes.
Glucokinase (GK) is an important enzyme for regulating blood glucose levels and a potentially attractive target for diabetes of the young type 2 and persistent hyperinsulinemic hypoglycemia of infancy.
Here we report linkage between the glucokinase locus on chromosome 7p and diabetes in 16 French families with maturity-onset diabetes of the young, a form of NIDDM characterized by monogenic autosomal dominant transmission and early age of onset.
In contrast, inactivating mutations of GCK result in diabetes, including a mild form (MODY2) and a severe form (permanent neonatal diabetes mellitus (PNDM)).
We aimed to assess the prevalence of diabetic retinopathy (DR) in adult patients with GCK-MODY and HNF1A-MODY in Poland and to identify biochemical and clinical risk factors associated with its occurrence.We examined 74 GCK mutation carriers, 51 with diabetes and 23 with prediabetes, respectively, and 63 patients with HNF1A-MODY.
Mutations in the transcription factors HNF1A and HNF4A and in the β-cell potassium ATP channel components cause diabetes which responds to low dose and high dose sulfonylurea agents, respectively, while glucokinase mutations require no treatment.