A good metabolic control of type 1 diabetes mellitus (T1DM) is crucial to avoid long-term complications associated with the disease. Although recent evidences suggest that a good metabolic control of T1DM is partly independent of management intensity and could be anticipated since onset, factors that influence glycated haemoglobin (HbA1c) patterns remain poorly understood and are likely to be genetic.

While significant progress has been made in understanding of the genetic contribution to T1DM onset, very few studies have evaluated the role of genetic factors on T1DM metabolic control.

This study aims to create a comprehensive database of genetic and phenotypic data in a cohort of children and young adults with T1DM and to evaluate genetic and environmental factors that might predict trajectories in glycemic control

Inclusion Criteria

Cases:

• age between 6 and 21 years;
• patients suffering from type 1 diabetes

Controls:

• age between 6 and 21 years;
• patients for whom a venous sampling is planned

Exclusion criteria

Cases:

• patients for whom it is not possible to collect information on the clinical history, starting from the onset of diabetes
• patients with other types of diabetes mellitus (type 2, monogenic diabetes, diabetes related to cystic fibrosis...)
• patients incapable of expressing valid informed consent or whose parents are incapable of expressing valid informed consent.

Controls:

• subjects with type 1 and 2 diabetes
• obese subjects and those with a family history of diabetes and obesity or other metabolic disorders
• subjects with HbA1c >6%
• patients incapable of expressing valid informed consent or whose parents are incapable of expressing valid informed consent.

Patients between 6 and 21 years with or without type 1 diabetes