Background: Maturity-onset diabetes of the young (MODY) is a monogenic form of diabetes that accounts for 25% of all cases but it is underestimated because its often misdiagnosed as T1D or T2D whose symptoms are often overlapping. It is a phenotypically and genetically heterogeneous disorder characterised by autosomal dominant inheritance, a young age of onset and pancreatic β-cell dysfunction.
Objective and hypotheses: Actually in about 50% of MODY patients is not identified causative mutations in known genes (MODYx). Recent advances in next-generation sequencing technologies make it affordable to search for rare and functional variants for common complex diseases systematically. On the bases of this observation, we decide to analyse 100 MODY patients through next generation sequencing (NGS) tecnology.
Method: A set of 182 genes were chosen for targeted resequencing (454 Roche platform). We selected genes known implicated in the pathway of pancreatic β cells, candidate genes for T2D, and genes causative of diabetes in mice experiments.
Results: In the 66% of cases we found, in association with known heterozygous/homozygous SNPs associated with diabetes, rare and pathogenetic variants, demonstrating that this approach leads to a genetic diagnosis in most of patients. Moreover, two mutations were identified in different genes in 40% of cases suggesting a complex etiology.
Conclusion: The increased number of genes tested led to a higher mutation detection rate. This approach may help in understanding the molecular aetiology of diabetes and in providing a more personalised treatment for each genetic subtype.
10 - 12 Sep 2016
European Society for Paediatric Endocrinology