Cognitive Neuroscience, Department of Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran.
Physiology, Department of Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran.
Tabriz Child and Adolescent Psychiatrist, Tabriz University of Medical Sciences, Tabriz, Iran.
Radiobiology, Department of Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran.
Attention deficit hyperactivity disorder (ADHD) is a multi-factorial disorder that has defined by hyperactivity, impulsivity and attention deficits. Various neurotransmitters such as dopamine can play a role in its pathophysiology. The aim of this study was to examine the association of two common single nucleotide polymorphisms in DRD2 gene, Taq I A (T/C) and Taq I B (G/A), with ADHA risk among Iranian-Azeri population.
Materials and Methods
A study of case–control association was performed with 89 samples with attention deficit hyperactivity disorder and 96 healthy subjects. Peripheral blood samples were used for Genomic DNA extraction by salting-out method. SNP genotyping was carried out by PCR-RFLP technique. The collected data were analyzed through javastant online statistics software, using Chi-square, with a significance level of 0.05.
There was not a significant difference in the allele and genotype frequencies between ADHD and Taq1B polymorphism in cases and controls (P>0.05). In the Taq IA of DRD2 gene, TT homozygous dominants and CC homozygous recessives were more frequent in case group than in control group but significant difference was not observed (P>0.05). Also, T/C heterozygotes were more frequent among the control group than the case group, and difference was significant (P<0.05).
Our data supports lack of association between Taq1A and Taq1B gene polymorphisms and ADHD.