ABSTRACT
We studied a variable number tandem repeat polymorphism within the dopamine transporter gene (DAT) for an association with Parkinson's disease in a Chinese population. Five alleles were detected, consisting of 6, 8, 9, 10, and 11 copies of the 40 base pair repeat sequence. The 10-copy allele was most common, accounting for 90% of alleles. There were no significant differences between the patients and the control subjects in the distribution frequencies of the alleles or genotypes. Therefore, this polymorphism is not associated with Parkinson's disease in Chinese populations.
Subject(s)
Asian People/genetics , Carrier Proteins/genetics , Membrane Glycoproteins , Membrane Transport Proteins , Nerve Tissue Proteins , Parkinson Disease/genetics , Aged , Aged, 80 and over , Alleles , China/ethnology , Dopamine Plasma Membrane Transport Proteins , Female , Gene Frequency , Genotype , Hong Kong/ethnology , Humans , Male , Middle Aged , Parkinson Disease/ethnologyABSTRACT
The presynaptic dopamine transporter in nigral dopaminergic neurons confers susceptibility to the cytotoxic effects of the neurotoxic metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Polymorphisms in the dopamine transporter might influence the susceptibility to such toxins. Therefore, we investigated whether a polymorphic region in the 3'-untranslated region of the dopamine-transporter gene is associated with idiopathic Parkinson's disease (PD). The frequency distribution of the alleles was significantly different between the patients (n = 100) and controls (n = 200, p < 0.05). The rare 11-copy allele was more common in the patients (odds ratio = 10.2, 95% confidence interval - 1.2-87.9, p < 0.025). The susceptibility of some people to PD may be conferred by polymorphisms in the dopamine-transporter gene that could lead to increased cellular accumulation of neurotoxic compounds in dopaminergic neurons.
