Variable number tandem repeat dopamine transporter gene polymorphism and Parkinson's disease: no association found.

We studied a variable number of tandem repeat polymorphisms in the dopamine transporter gene in search of an association with Parkinson's disease in a French population. Five alleles were detected, consisting of 7, 8, 9, 10 and 11 copies of the 40-base pair repeat sequence, of which the 10-copy allele was the most common. There was no significant difference between the patients and the control subjects in the distribution frequencies of the alleles or genotypes, or in ages at onset in patients between the main allelic classes.