Another region important for AD+DD was observed where the 3′ regions of DRD2 and ANKK1 meet (Table 5). The risk variants were the significant individual risk haplotype G-G-G-G-G in A6-D3 (pihs = 0.0093) identified in the family sample, or G-C-G-G-G in A4-D1 (pihs = 0.0087) in the case-control sample. All 11 risk haplotypes (pihs = 0.017 ~ 0.0028) share the same polymorphic nucleotides at the corresponding SNP loci, consistent with all of them identifying the same risk locus, i.e., the locus was tagged with the same set of markers. The various risk haplotypes, between samples from the two designs, overlapped for 3 SNPs (A6-D1). This common region includes the region of DRD2^C957T (rs6277) in exon 7 of DRD2, and SNP-A6 and SNP-A7 (rs4938016 and rs1800497) in exon 8 of ANKK1.
