DNA methylation profile of peripheral blood in attention deficit hyperactivity disorder (ADHD) carriers by array

Abstract

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common childhood brain disorders and can continue through adolescence and adulthood affects approximately 5.3% of children worldwide. Despite the prevalence and heritability ADHD, biological markers do not exist. Behavioral genetic studies have demonstrated conclusively that genetic influences play a role in the etiology of ADHD. Similarly, environmental factors also play an important role in the etiology of ADHD. DNA methylation is an important epigenetic mechanism associated with transcriptional silencing of genes in CpG islands. Therefore, it is essential to investigate whether the genetic alterations of ADHD are related to the activation or inactivation of genes by DNA methylation. For the study, individuals (n=30) up to 16 years of age with a clinical diagnosis of ADHD and their parents will be recruited in the Unit of Genetics of the Institute of Child, Hospital das Clínicas of the FMUSP (HC-FMUSP). Blood samples will be collected, and the extraction of lymphocyte DNA will be performed. Methylation assays will be carried out by array to verify the methylation status of CpG islands in thousands of genomic regions. In addition, the SNP array in order to better understanding of the findings will be performed. Data will be analyzed using GenomeStudio software and specific packages within the environment R. Finally, the relationships between epigenetic data obtained and the phenotype of individuals with ADHD will be made in order to obtain a DNA methylation profile of peripheral blood in individuals with ADHD. (AU)