However, the boys with ADHD had higher BDNF levels than the healthy controls boys (Figure 1A) (ADHD: 4.57 ± 4.43 ng/mL vs. Controls: 3.17 ± 3.84 ng/mL, p = 0.027, Standardized Test Statistic = 2.210) and the girls with ADHD had lower BDNF levels than the healthy control girls (ADHD: 3.01 ± 2.99 ng/mL vs. Controls: 4.69 ± 4.36 ng/mL, p = 0.014, Standardized Test Statistic = 2.458). This evidence concerns the gene BDNF and attention deficit-hyperactivity disorder.