From Rare Copy Number Variants to Biological Processes in ADHD

Area of Science:

• Genetics
• Neuroscience
• Bioinformatics

Background:

• Attention deficit hyperactivity disorder (ADHD) is a complex psychiatric disorder with a strong genetic component.
• Identifying specific genes and molecular pathways involved in ADHD is crucial for understanding its etiology.

Purpose of the Study:

• To identify ADHD-associated candidate genes and their molecular modules using rare genetic variants.
• To explore the biological themes and pathways implicated in ADHD pathogenesis.

Main Methods:

• Integrated analysis of copy number variation (CNV) data from 6,176 ADHD cases and 25,026 controls.
• Prioritized genes based on recurrence, absence in controls, CNV overlap, protein-protein interactions, and cross-species annotation.
• Applied bioinformatic methods to identify coexpressed genes, protein modules, and validated findings with genome-wide association studies.

Main Results:

• Localized 2,241 eligible genes within reported CNVs, classifying 432 as high-priority ADHD candidate genes.
• Identified significant coexpression of high-priority genes in the brain and a network of 66 genes linked to ADHD phenotypes.
• Discovered four interconnected protein modules and pinpointed 26 genes across all bioinformatic analyses, including *POLR3C* and *RBFOX1* supported by common variants.

Conclusions:

• A combined approach of stringent CNV filtering and bioinformatics effectively identifies credible ADHD candidate genes.
• The study offers insights into the molecular mechanisms of ADHD, prioritizing genes for further functional validation.
• This pipeline advances the genetic understanding of ADHD and aids in identifying potential therapeutic targets.