Dopamine transporter 1 (DAT1) rs40184 single nucleotide polymorphism is not associated with the Malaysian major depressive disorder subjects

Major depressive disorder (MDD) is a serious mental illness with a multifactorial aetiology that was shown to influence behaviour and affect cognition. Previous research has favoured the involvement of dopamine in the aetiology of the disorder, and since one of the critical regulators of the dopamine levels and activity in the brain is DAT1, the present study investigated the association of a single nucleotide polymorphism in the DAT1 gene (rs40184) and MDD in the Malaysian population. A total of 300 cases and 300 matched controls were recruited from four Klang valley hospitals and were screened for DAT1 rs40184 using high resolution melting assays. The allele and genotype frequencies were analysed by using Chi-square. Hardy Weinberg equilibrium for the distribution of alleles and genotypes was tested by using Chi-square. Determination of the association between rs40184 and MDD was achieved by conditional logistic regression using SPSS. In the present study, no significant association was obtained between DAT1 and MDD in the Malaysian population.