Association between SNPs and haplotypes mapping to 6p21 and BCP-ALL risk. The x-axis represents the position of each SNP; the y-axis, P values on a minus logarithmic scale. Cochran-Armitage trend test statistics are shown in black for directly genotyped SNPs and in gray for imputed SNPs in the top panel. Lines in the bottom panel correspond to haplotype test statistics: blue defined by 5 SNPs and red by 12 SNPs. Relative positions of the major HLA genes are also shown. Chromosomal coordinates were derived from the National Center for Biotechnology Information, build 36. See the complete figure in the article by Hosking et al beginning on page 1633.