Lack of association between the Y chromosome haplogroups and attention deficit hyperactivity disorder (ADHD) in Korean boys.

Attention deficit hyperactivity disorder (ADHD) is a major neurodevelopmental disorder including multiple environmental and biological causes. It is generally reported that the prevalence of ADHD is 4-fold higher in boys than in girls. Previous studies have reported that the Y-linked genes have been significantly associated with neuropsychiatric disorders. Furthermore, several Y chromosome haplogroups have been reported to be related to the development of ADHD symptoms. Therefore, we analyzed the genetic correlation between the Y chromosome haplogroups and ADHD in the Korean boys. Our results showed that the Y chromosome haplogroup O2b (xO2b1) (p = 0.053) and O3a3c1 (p = 0.050) has a trend of borderline statistical significance. In subtype analysis, a significant association was observed between haplogroup O3a3c1 and the ADHD/C [odds ratio (OR), 3.43; 95 % confidence interval (CI), 1.336 - 8.782; p = 0.007]. However, this association could not pass the Bonferroni correction for multiple testing. In conclusion, our results showed a lack of association between Y chromosome haplogroups and the occurrence of ADHD in Korean boys.