CPB2 5′-flanking region SNPs and haplotypes examined in this study. The H1 to H4 haplotypes are those described by Henry and coworkers.²⁷  The haplotypes denoted H1* to H4* have the substitutions corresponding to a second block of SNPs (shaded) reported by Franco and coworkers.²⁸  The linkage relationship of the relatively infrequent −298 G/A SNP to the other SNPs is not known. The H1 haplotype (wt) corresponds to the sequence of the 5′-flanking region originally reported by Boffa and coworkers.³¹