[Association of dopamine beta-hydroxylase polymorphism with attention deficit hyperactivity disorder in children]

To study the association of dopamine beta-hydroxylase gene 5' flanking region polymorphism-1021 C-->T with attention deficit hyperactivity disorder (ADHD) in Han children.

ADHD was diagnosed according to the DSM-IV criteria. DNA was extracted and PCR was performed to examine the DBH-1021C-->T polymorphism. HHRR was used to test the association of dopamine beta-hydroxylase gene with different subtypes of ADHD.

HHRR results showed this polymorphism had a tendency to be associated with the inattention subtype (P=0.067) and the combined subtype (P=0.076). The T allele was the protective factor of the inattentive subtype (P=0.07), and the risk factor of the combined subtype (P=0.08). After dividing the 292 nuclear families according to sex, DBH-1021C-->T polymorphism was found to be associated with the combined subtype (P=0.04) with the T allele as the risk factor (P=0.02). There were no positive findings among the girl nuclear families of ADHD.

DBH gene is related to ADHD combined subtype and inattention subtype. The genetic basis of ADHD combined subtype and is inattention is different, and is influenced by sex factor.