The human dopamine transporter gene: the 5 '-flanking region reveals five diallelic polymorphic sites in a Caucasian population sample

The 5'-flanking region of the human dopamine transporter (hDAT) was systema tically screened for variants by single strand conformation analysis (SSCA) between -1586 and +97 basepair (bp) relative to the transcription start si te. Five diallelic polymorphisms were found, which were shown to be due to single base substitutions: T-67A, G-660C, C-839T, C-1169G, T-1476G. In a po pulation sample of 119 unrelated Caucasians, allele frequencies of the rare r allele were 47% for -67T, 3% for -660C, 45% for -839T, 50% for -1169G, an d 8% for -1476G, respectively. Among 15 observed haplotypes, seven haplotyp es collected a frequency of about 96% in our sample. T-67A, C-839T, C-1169G , T-1476G were related to potential transcriptional recognition sites. Thes e findings and the occurrence of distinct haplotypes at the hDAT promoter l ocus in a Caucasian population sample make this region a promising target i n the context of linkage a nd association studies in certain diseases. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.