Haplotype analyses were conducted by likelihood-based association analysis using the Unphased program [50], also direct molecular haplotyping was applied for the DRD4 promoter -616 C/G and -521 C/T SNPs [46]. Linkage disequilibrium between the DRD2 SNPs was calculated by the Haploview program [51] using the Hungarian control sample genotype data: the DRD2 TaqIB SNP was in linkage with TaqIA (D'= 0.947, LOD = 29.77, r2 = 0.701) and with TaqID (D'= 1.0, LOD = 12.17, r2 = 0.212). Linkage disequilibrium for the DRD4 promoter polymorphisms has been previously reported [46].
