This noninterventional study will assess genomic changes in the metabotropic glutamate receptor (mGluR) network in children and adolescents with ADHD.

Male and female subjects 6 to 17 years of age with a primary psychiatric diagnosis of ADHD will be enrolled in this study. The subject and his or her parent/guardian must agree to genotyping to determine whether the subject has disruptive mutations within any of the approximately 274 mGluR-network genes, and complete an interview that will include information about the subject's ADHD history, treatment, and co-morbidities.

Inclusion Criteria:

• The subject is male or female ≥6 and ≤17 years of age.
• The subject has ADHD as defined by the Diagnostic and Statistical Manual of Mental Disorders, 5th edition.
• The subject, his or her legally responsible representative, and investigator agree to complete ADHD history, treatment, and comorbidity electronic case report form (eCRF).

Exclusion Criteria:

• The subject or parent/legal guardian is in the opinion of the investigator mentally or legally incapacitated and unable to provide informed consent/assent for participation in the study.

Subjects between the ages of 6 years and 17 years of age with a previously established diagnosis of ADHD will be eligible for screening.