The epidemiology, molecular pathogenesis, diagnosis, and treatment of maturity-onset diabetes of the young (MODY)

Abstract

Background: The most common type of monogenic diabetes is maturity-onset diabetes of the young (MODY), a clinically and genetically heterogeneous group of endocrine disorders that affect 1-5% of all patients with diabetes mellitus. MODY is characterized by autosomal dominant inheritance but de novo mutations have been reported. Clinical features of MODY include young-onset hyperglycemia, evidence of residual pancreatic function, and lack of beta cell autoimmunity or insulin resistance. Glucose-lowering medications are the main treatment options for MODY. The growing recognition of the clinical and public health significance of MODY by clinicians, researchers, and governments may lead to improved screening and diagnostic practices. Consequently, this review article aims to discuss the epidemiology, pathogenesis, diagnosis, and treatment of MODY based on relevant literature published from 1975 to 2020.

Main body: The estimated prevalence of MODY from European cohorts is 1 per 10,000 in adults and 1 per 23,000 in children. Since little is known about the prevalence of MODY in African, Asian, South American, and Middle Eastern populations, further research in non-European cohorts is needed to help elucidate MODY's exact prevalence. Currently, 14 distinct subtypes of MODY can be diagnosed through clinical assessment and genetic analysis. Various genetic mutations and disease mechanisms contribute to the pathogenesis of MODY. Management of MODY is subtype-specific and includes diet, oral antidiabetic drugs, or insulin.

Conclusions: Incidence and prevalence estimates for MODY are derived from epidemiologic studies of young people with diabetes who live in Europe, Australia, and North America. Mechanisms involved in the pathogenesis of MODY include defective transcriptional regulation, abnormal metabolic enzymes, protein misfolding, dysfunctional ion channels, or impaired signal transduction. Clinicians should understand the epidemiology and pathogenesis of MODY because such knowledge is crucial for accurate diagnosis, individualized patient management, and screening of family members.

Keywords: Beta cell; Diagnosis; MODY; Monogenic diabetes; Pathogenesis; Prevalence; Treatment.

Fig. 1

A systematic approach to the diagnosis of MODY. Diagnosis of MODY is a stepwise process guided by a high index of suspicion, clinical assessment, diabetes-specific tests, and comprehensive genetic testing. BMI: body mass index; FPG: fasting plasma glucose; GAD-65: glutamic acid decarboxylase-65 autoantibodies; HbA1c: glycated hemoglobin; HDL: high density lipoprotein; IAA: insulin autoantibodies; IA-2A: tyrosine phosphatase-related islet antigen-2 autoantibodies; LDL: low density lipoprotein; OADs: oral antidiabetic drugs; OGTT: oral glucose tolerance test; RCAD: renal cysts and diabetes; T1DM: type 1 diabetes mellitus; T2DM: type 2 diabetes mellitus; ZnT8: zinc transporter 8 autoantibodies