Citation

Karmakar A, Maitra S, Verma D, Chakraborti B, Goswami R, Ghosh P, Sinha S, Mohanakumar KP, Usha R, Mukhopadhyay K. Neurochem. Res. 2014; 39(5): 843-852.

Affiliation

Manovikas Biomedical Research and Diagnostic Centre, 482, Madudah, Plot I-24, Sec.-J, E.M. Bypass, Kolkata, 700107, India.

Copyright

(Copyright © 2014, Holtzbrinck Springer Nature Publishing Group)

DOI

10.1007/s11064-014-1276-4

PMID

24652311

Abstract

Attention deficit hyperactivity disorder (ADHD) is the most frequently diagnosed behavioral disorder in children with a high frequency of co-morbid conditions like conduct disorder (CD) and oppositional defiant disorder (ODD). These traits are controlled by neurotransmitters like dopamine, serotonin and norepinephrine. Monoamine oxidase A (MAOA), a mitochondrial enzyme involved in the degradation of amines, has been reported to be associated with aggression, impulsivity, depression, and mood changes. We hypothesized that MAOA can have a potential role in ADHD associated CD/ODD and analyzed 24 markers in a group of Indo-Caucasoid subjects. ADHD probands and controls (N = 150 each) matched for ethnicity and gender were recruited following the Diagnostic and Statistical Manual for Mental Disorders-IV. Appropriate scales were used for measuring CD and ODD traits. Markers were genotyped by PCR-based methods and data obtained analyzed using the Cocaphase program under UNPHASED. Only eight markers were found to be polymorphic. rs6323 "G" allele showed higher frequencies in ADHD (P = 0.0023), ADHD + CD (P = 0.03) and ADHD + ODD (P = 0.01) as compared to controls. Haplotype analysis revealed statistically significant difference for three haplotypes in ADHD cases (P < 0.02). Statistically significant differences were also noticed for haplotypes in ADHD + CD and ADHD + ODD cases (P < 0.01). LD analysis showed significant variation in different groups. Multidimensionality reduction analysis showed independent as well as interactive effects of markers. Genotypes showed correlation with behavioral problems in ADHD and ADHD + CD. We interpret that MAOA gene variants may contribute to the etiology of ADHD as well as associated co-morbid CD and ODD in this ethnic group.

Language: en