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1.
Nat Genet ; 50(8): 1122-1131, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30054598

RESUMO

The molecular mechanisms underpinning susceptibility loci for type 2 diabetes (T2D) remain poorly understood. Coding variants in peptidylglycine α-amidating monooxygenase (PAM) are associated with both T2D risk and insulinogenic index. Here, we demonstrate that the T2D risk alleles impact negatively on overall PAM activity via defects in expression and catalytic function. PAM deficiency results in reduced insulin content and altered dynamics of insulin secretion in a human ß-cell model and primary islets from cadaveric donors. Thus, our results demonstrate a role for PAM in ß-cell function, and establish molecular mechanisms for T2D risk alleles at this locus.

2.
Nat Genet ; 47(12): 1415-25, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26551672

RESUMO

We performed fine mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in or near KCNQ1. 'Credible sets' of the variants most likely to drive each distinct signal mapped predominantly to noncoding sequence, implying that association with T2D is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine mapping implicated rs10830963 as driving T2D association. We confirmed that the T2D risk allele for this SNP increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease.


Assuntos
Mapeamento Cromossômico , Diabetes Mellitus Tipo 2/genética , Loci Gênicos , Predisposição Genética para Doença , Fator 3-beta Nuclear de Hepatócito/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor MT2 de Melatonina/genética , Sítios de Ligação , Estudos de Casos e Controles , Imunoprecipitação da Cromatina , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Genômica , Fator 3-beta Nuclear de Hepatócito/metabolismo , Humanos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Fígado/metabolismo , Fígado/patologia , Anotação de Sequência Molecular , Receptor MT2 de Melatonina/metabolismo
3.
Curr Opin Lipidol ; 26(2): 88-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25692341

RESUMO

PURPOSE OF REVIEW: Glucokinase regulator (GCKR) encodes glucokinase regulatory protein (GKRP), a hepatocyte-specific inhibitor of the glucose-metabolizing enzyme glucokinase (GCK). Genome-wide association studies have identified a common coding variant within GCKR associated with multiple metabolic traits. This review focuses on recent insights into the critical role of GKRP in hepatic glucose metabolism that have stemmed from the study of human genetics. This knowledge has improved our understanding of glucose and lipid physiology and informed the development of targeted molecular therapeutics for diabetes. RECENT FINDINGS: Rare GCKR variants have effects on GKRP expression, localization, and activity. These variants are collectively associated with hypertriglyceridaemia but are not causal. Crystal structures of GKRP and the GCK-GKRP complex have been solved, providing greater insight into the molecular interactions between these proteins. Finally, small molecules have been identified that directly bind GKRP and reduce blood glucose levels in rodent models of diabetes. SUMMARY: GCKR variants across the allelic spectrum have effects on glucose and lipid homeostasis. Functional analysis has highlighted numerous molecular mechanisms for GKRP dysfunction. Hepatocyte-specific GCK activation via small molecule GKRP inhibition may be a new avenue for type 2 diabetes treatment, particularly considering evidence indicating GKRP loss-of-function alone does not cause hypertriglyceridaemia.


Assuntos
Proteínas de Transporte/fisiologia , Glucose/metabolismo , Triglicerídeos/metabolismo , Animais , Proteínas de Transporte/antagonistas & inibidores , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/enzimologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Homeostase , Humanos , Terapia de Alvo Molecular , Mutação de Sentido Incorreto
4.
Obesity (Silver Spring) ; 22(12): 2621-4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25234154

RESUMO

OBJECTIVE: Several deletions of chromosome 6q, including SIM1, were reported in obese patients with developmental delay. Furthermore, rare loss-of-function SIM1 mutations were shown to contribute to severe obesity, yet the role of these mutations in developmental delay remained unclear. Here, SIM1 in children with neurodevelopmental abnormalities was screened and the functional effect of the identified mutations was investigated. METHODS: SIM1 was sequenced in 283 children presenting with developmental delay and at least overweight. The effect of the identified mutations on SIM1 transcriptional activity in stable human cell lines was assessed using luciferase gene reporter assays. RESULTS: Two novel mutations (c.886A>G/p.R296G and c.925A>G/p.S309G) in two boys with variable degrees of cognitive deficits and weight issues were identified. The child mutated for p.R296G presented with a generally more severe phenotype than the p.S309G carrier (obesity, compulsive eating, neonatal hypotonia versus overweight only), while both mutations had strong loss-of-function effects on SIM1 transcriptional activity. CONCLUSIONS: Severe loss-of-function SIM1 mutations can be associated with a spectrum of developmental delay phenotypes and obesity. Our data suggest that SIM1 sequencing should be performed more systematically in patients with developmental delay, even in the absence of severe obesity. These results deserve further SIM1 screening studies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Deficiências do Desenvolvimento/genética , Obesidade Mórbida/genética , Proteínas Repressoras/genética , Criança , Análise Mutacional de DNA , Deficiências do Desenvolvimento/complicações , Feminino , Humanos , Luciferases/genética , Masculino , Obesidade Mórbida/complicações , Obesidade Mórbida/fisiopatologia , Fenótipo , Ativação Transcricional
5.
Hum Mol Genet ; 23(24): 6432-40, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25015100

RESUMO

Mutations in glucokinase (GCK) cause a spectrum of glycemic disorders. Heterozygous loss-of-function mutations cause mild fasting hyperglycemia irrespective of mutation severity due to compensation from the unaffected allele. Conversely, homozygous loss-of-function mutations cause permanent neonatal diabetes requiring lifelong insulin treatment. This study aimed to determine the relationship between in vitro mutation severity and clinical phenotype in a large international case series of patients with homozygous GCK mutations. Clinical characteristics for 30 patients with diabetes due to homozygous GCK mutations (19 unique mutations, including 16 missense) were compiled and assigned a clinical severity grade (CSG) based on birth weight and age at diagnosis. The majority (28 of 30) of subjects were diagnosed before 9 months, with the remaining two at 9 and 15 years. These are the first two cases of a homozygous GCK mutation diagnosed outside infancy. Recombinant mutant GCK proteins were analyzed for kinetic and thermostability characteristics and assigned a relative activity index (RAI) or relative stability index (RSI) value. Six of 16 missense mutations exhibited severe kinetic defects (RAI ≤ 0.01). There was no correlation between CSG and RAI (r(2) = 0.05, P = 0.39), indicating that kinetics alone did not explain the phenotype. Eighty percent of the remaining mutations showed reduced thermostability, the exceptions being the two later-onset mutations which exhibited increased thermostability. Comparison of CSG with RSI detected a highly significant correlation (r(2) = 0.74, P = 0.002). We report the largest case series of homozygous GCK mutations to date and demonstrate that they can cause childhood-onset diabetes, with protein instability being the major determinant of mutation severity.


Assuntos
Diabetes Mellitus/genética , Glucoquinase/genética , Mutação de Sentido Incorreto , Fenótipo , Idade de Início , Peso ao Nascer , Criança , Pré-Escolar , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/enzimologia , Diabetes Mellitus/patologia , Ensaios Enzimáticos , Estabilidade Enzimática , Feminino , Genótipo , Glucoquinase/metabolismo , Homozigoto , Temperatura Alta , Humanos , Lactente , Recém-Nascido , Cinética , Masculino , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Índice de Gravidade de Doença
6.
Hum Mol Genet ; 23(20): 5570-8, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24879641

RESUMO

Significant resources have been invested in sequencing studies to investigate the role of rare variants in complex disease etiology. However, the diagnostic interpretation of individual rare variants remains a major challenge, and may require accurate variant functional classification and the collection of large numbers of variant carriers. Utilizing sequence data from 458 individuals with hypertriglyceridemia and 333 controls with normal plasma triglyceride levels, we investigated these issues using GCKR, encoding glucokinase regulatory protein. Eighteen rare non-synonymous GCKR variants identified in these 791 individuals were comprehensively characterized by a range of biochemical and cell biological assays, including a novel high-throughput-screening-based approach capable of measuring all variant proteins simultaneously. Functionally deleterious variants were collectively associated with hypertriglyceridemia, but a range of in silico prediction algorithms showed little consistency between algorithms and poor agreement with functional data. We extended our study by obtaining sequence data on family members; however, functional variants did not co-segregate with triglyceride levels. Therefore, despite evidence for their collective functional and clinical relevance, our results emphasize the low predictive value of rare GCKR variants in individuals and the complex heritability of lipid traits.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Hiperlipoproteinemia Tipo IV/genética , Polimorfismo de Nucleotídeo Único , Triglicerídeos/sangue , Proteínas Adaptadoras de Transdução de Sinal/química , Algoritmos , Animais , Células COS , Estudos de Casos e Controles , Cercopithecus aethiops , Variação Genética , Células HeLa , Humanos , Hiperlipoproteinemia Tipo IV/sangue , Camundongos , Modelos Moleculares , Estrutura Terciária de Proteína , Análise de Sequência de DNA
7.
Biochem J ; 461(3): 403-12, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24814368

RESUMO

The bHLH (basic helix-loop-helix) PAS (Per/Arnt/Sim) transcription factor SIM1 (single-minded 1) is important for development and function of regions of the hypothalamus that regulate energy homoeostasis and the feeding response. Low-activity SIM1 variants have been identified in individuals with severe early-onset obesity, but the underlying molecular causes of impaired function are unknown. In the present study we assess a number of human SIM1 variants with reduced activity and determine that impaired function is frequently due to defects in dimerization with the essential partner protein ARNT2 (aryl hydrocarbon nuclear translocator 2). Equivalent variants generated in the highly related protein SIM2 (single-minded 2) produce near-identical impaired function and dimerization defects, indicating that these effects are not unique to the structure of SIM1. On the basis of these data, we predict that other select SIM1 and SIM2 variants reported in human genomic databases will also be deficient in activity, and identify two new low-activity SIM1 variants (V290E and V326F) present in the population. The cumulative data is used in homology modelling to make novel observations about the dimerization interface between the PAS domains of SIM1 and ARNT2, and to define a mutational 'hot-spot' in SIM1 that is critical for protein function.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Núcleo Celular/metabolismo , Modelos Moleculares , Polimorfismo de Nucleotídeo Único , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Translocador Nuclear Receptor Aril Hidrocarboneto/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Núcleo Celular/ultraestrutura , Bases de Dados Genéticas , Células HEK293 , Humanos , Imuno-Histoquímica , Imunoprecipitação , Dados de Sequência Molecular , Mutação , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Transporte Proteico , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/genética , Alinhamento de Sequência
8.
J Clin Endocrinol Metab ; 99(6): E1067-71, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24606082

RESUMO

BACKGROUND: Maturity-onset diabetes of the young (MODY) is uncommon; however, accurate diagnosis facilitates personalized management and informs prognosis in probands and relatives. OBJECTIVE: The objective of the study was to highlight that the appropriate use of genetic and nongenetic investigations leads to the correct classification of diabetes etiology. CASE DISCUSSION: A 30-year-old European female was diagnosed with insulin-treated gestational diabetes. She discontinued insulin after delivery; however, her fasting hyperglycemia persisted. ß-Cell antibodies were negative and C-peptide was 0.79 nmol/L. Glucokinase (GCK)-MODY was suspected and confirmed by the identification of a GCK mutation (p.T206M). METHODS: Systematic clinical and biochemical characterization and GCK mutational analysis were implemented to determine the diabetes etiology in five relatives. Functional characterization of GCK mutations was performed. RESULTS: Identification of the p.T206M mutation in the proband's sister confirmed a diagnosis of GCK-MODY. Her daughter was diagnosed at 16 weeks with permanent neonatal diabetes (PNDM). Mutation analysis identified two GCK mutations that were inherited in trans-p. [(R43P);(T206M)], confirming a diagnosis of GCK-PNDM. Both mutations were shown to be kinetically inactivating. The proband's mother, other sister, and daughter all had a clinical diagnosis of type 1 diabetes, confirmed by undetectable C-peptide levels and ß-cell antibody positivity. GCK mutations were not detected. CONCLUSIONS: Two previously misclassified family members were shown to have GCK-MODY, whereas another was shown to have GCK-PNDM. A diagnosis of type 1 diabetes was confirmed in three relatives. This family exemplifies the importance of careful phenotyping and systematic evaluation of relatives after discovering monogenic diabetes in an individual.


Assuntos
Diabetes Mellitus Tipo 2/classificação , Diabetes Mellitus Tipo 2/etiologia , Diabetes Gestacional/diagnóstico , Transtornos Puerperais/diagnóstico , Adulto , Diabetes Mellitus Tipo 2/genética , Feminino , Humanos , Linhagem , Gravidez
9.
PLoS One ; 9(2): e89335, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24586696

RESUMO

Recent genetic and clinical evidence has implicated glucokinase regulatory protein (GKRP) in the pathogenesis of type 2 diabetes and related traits. The primary role of GKRP is to bind and inhibit hepatic glucokinase (GCK), a critically important protein in human health and disease that exerts a significant degree of control over glucose metabolism. As activation of GCK has been associated with improved glucose tolerance, perturbation of the GCK-GKRP interaction represents a potential therapeutic target for pharmacological modulation. Recent structural and kinetic advances are beginning to provide insight into the interaction of these two proteins. However, tools to comprehensively assess the GCK-GKRP interaction, particularly in the context of small molecules, would be a valuable resource. We therefore developed three robust and miniaturized assays for assessing the interaction between recombinant human GCK and GKRP: an HTRF assay, a diaphorase-coupled assay, and a luciferase-coupled assay. The assays are complementary, featuring distinct mechanisms of detection (luminescence, fluorescence, FRET). Two assays rely on GCK enzyme activity modulation by GKRP while the FRET-based assay measures the GCK-GKRP protein-protein interaction independent of GCK enzymatic substrates and activity. All three assays are scalable to low volumes in 1536-well plate format, with robust Z' factors (>0.7). Finally, as GKRP sequesters GCK in the hepatocyte nucleus at low glucose concentrations, we explored cellular models of GCK localization and translocation. Previous findings from freshly isolated rat hepatocytes were confirmed in cryopreserved rat hepatocytes, and we further extended this study to cryopreserved human hepatocytes. Consistent with previous reports, there were several key differences between the rat and human systems, with our results suggesting that human hepatocytes can be used to interrogate GCK translocation in response to small molecules. The assay panel developed here should help direct future investigation of the GCK-GKRP interaction in these or other physiologically relevant human systems.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Ensaios Enzimáticos/métodos , Glucoquinase/metabolismo , Hepatócitos/citologia , Animais , Criopreservação/métodos , Interpretação Estatística de Dados , Fluorescência , Transferência Ressonante de Energia de Fluorescência , Técnicas Histológicas , Humanos , Processamento de Imagem Assistida por Computador , Luciferases , NADH Desidrogenase , Ratos
10.
Biochem J ; 459(3): 551-64, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24568320

RESUMO

Hepatic glucose phosphorylation by GK (glucokinase) is regulated by GKRP (GK regulatory protein). GKRP forms a cytosolic complex with GK followed by nuclear import and storage, leading to inhibition of GK activity. This process is initiated by low glucose, but reversed nutritionally by high glucose and fructose or pharmacologically by GKAs (GK activators) and GKRPIs (GKRP inhibitors). To study the regulation of this process by glucose, fructose-phosphate esters and a GKA, we measured the TF (tryptophan fluorescence) of human WT (wild-type) and GKRP-P446L (a mutation associated with high serum triacylglycerol) in the presence of non-fluorescent GK with its tryptophan residues mutated. Titration of GKRP-WT by GK resulted in a sigmoidal increase in TF, suggesting co-operative PPIs (protein-protein interactions) perhaps due to the hysteretic nature of GK. The affinity of GK for GKRP was decreased and binding co-operativity increased by glucose, fructose 1-phosphate and GKA, reflecting disruption of the GK-GKRP complex. Similar studies with GKRP-P446L showed significantly different results compared with GKRP-WT, suggesting impairment of complex formation and nuclear storage. The results of the present TF-based biophysical analysis of PPIs between GK and GKRP suggest that hepatic glucose metabolism is regulated by a metabolite-sensitive drug-responsive co-operative molecular switch, involving complex formation between these two allosterically regulated proteins.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Glucoquinase/metabolismo , Modelos Moleculares , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Regulação Alostérica , Substituição de Aminoácidos , Frutosefosfatos/metabolismo , Glucoquinase/química , Glucoquinase/genética , Glucose/metabolismo , Humanos , Ligantes , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Redobramento de Proteína , Estabilidade Proteica , Transporte Proteico , Desdobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Espectrometria de Fluorescência , Triptofano/química
11.
J Clin Invest ; 123(7): 3037-41, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23778136

RESUMO

Sim1 haploinsufficiency in mice induces hyperphagic obesity and developmental abnormalities of the brain. In humans, abnormalities in chromosome 6q16, a region that includes SIM1, were reported in obese children with a Prader-Willi-like syndrome; however, SIM1 involvement in obesity has never been conclusively demonstrated. Here, SIM1 was sequenced in 44 children with Prader-Willi-like syndrome features, 198 children with severe early-onset obesity, 568 morbidly obese adults, and 383 controls. We identified 4 rare variants (p.I128T, p.Q152E, p.R581G, and p.T714A) in 4 children with Prader-Willi-like syndrome features (including severe obesity) and 4 other rare variants (p.T46R, p.E62K, p.H323Y, and p.D740H) in 7 morbidly obese adults. By assessing the carriers' relatives, we found a significant contribution of SIM1 rare variants to intra-family risk for obesity. We then assessed functional effects of the 8 substitutions on SIM1 transcriptional activities in stable cell lines using luciferase gene reporter assays. Three mutations showed strong loss-of-function effects (p.T46R, p.H323Y, and p.T714A) and were associated with high intra-family risk for obesity, while the variants with mild or no effects on SIM1 activity were not associated with obesity within families. Our genetic and functional studies demonstrate a firm link between SIM1 loss of function and severe obesity associated with, or independent of, Prader-Willi-like features.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Mutação de Sentido Incorreto , Obesidade Mórbida/genética , Síndrome de Prader-Willi/genética , Proteínas Repressoras/genética , Adulto , Estudos de Casos e Controles , Pré-Escolar , Análise Mutacional de DNA , Feminino , Expressão Gênica , Frequência do Gene , Genes Reporter , Estudos de Associação Genética , Células HEK293 , Humanos , Lactente , Luciferases/biossíntese , Luciferases/genética , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Ativação Transcricional , Adulto Jovem
12.
J Clin Invest ; 123(7): 3042-50, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23778139

RESUMO

Single-minded 1 (SIM1) is a basic helix-loop-helix transcription factor involved in the development and function of the paraventricular nucleus of the hypothalamus. Obesity has been reported in Sim1 haploinsufficient mice and in a patient with a balanced translocation disrupting SIM1. We sequenced the coding region of SIM1 in 2,100 patients with severe, early onset obesity and in 1,680 controls. Thirteen different heterozygous variants in SIM1 were identified in 28 unrelated severely obese patients. Nine of the 13 variants significantly reduced the ability of SIM1 to activate a SIM1-responsive reporter gene when studied in stably transfected cells coexpressing the heterodimeric partners of SIM1 (ARNT or ARNT2). SIM1 variants with reduced activity cosegregated with obesity in extended family studies with variable penetrance. We studied the phenotype of patients carrying variants that exhibited reduced activity in vitro. Variant carriers exhibited increased ad libitum food intake at a test meal, normal basal metabolic rate, and evidence of autonomic dysfunction. Eleven of the 13 probands had evidence of a neurobehavioral phenotype. The phenotypic similarities between patients with SIM1 deficiency and melanocortin 4 receptor (MC4R) deficiency suggest that some of the effects of SIM1 deficiency on energy homeostasis are mediated by altered melanocortin signaling.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Mutação de Sentido Incorreto , Obesidade/genética , Proteínas Repressoras/genética , Adolescente , Estatura/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Expressão Gênica , Genes Reporter , Estudos de Associação Genética , Células HEK293 , Heterozigoto , Humanos , Lactente , Luciferases de Renilla/biossíntese , Luciferases de Renilla/genética , Masculino , Modelos Moleculares , Obesidade/patologia , Linhagem , Receptor Tipo 4 de Melanocortina/deficiência , Ativação Transcricional
13.
Diabetes Care ; 35(7): 1482-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22611063

RESUMO

OBJECTIVE: To demonstrate the importance of using a combined genetic and functional approach to correctly interpret a genetic test for monogenic diabetes. RESEARCH DESIGN AND METHODS: We identified three probands with a phenotype consistent with maturity-onset diabetes of the young (MODY) subtype GCK-MODY, in whom two potential pathogenic mutations were identified: [R43H/G68D], [E248 K/I225M], or [G261R/D217N]. Allele-specific PCR and cosegregation were used to determine phase. Single and double mutations were kinetically characterized. RESULTS: The mutations occurred in cis (double mutants) in two probands and in trans in one proband. Functional studies of all double mutants revealed inactivating kinetics. The previously reported GCK-MODY mutations R43H and G68D were inherited from an affected father and unaffected mother, respectively. Both our functional and genetic studies support R43H as the cause of GCK-MODY and G68D as a neutral rare variant. CONCLUSIONS: These data highlight the need for family/functional studies, even for previously reported pathogenic mutations.


Assuntos
Diabetes Mellitus Tipo 2/genética , Glucoquinase/genética , Feminino , Testes Genéticos , Heterozigoto , Humanos , Masculino , Mutação de Sentido Incorreto , Linhagem
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