In this study, we investigated tag single nucleotide polymorphisms (tSNPs) so as to maximally represent CNR1 common variants in the population. Twelve tSNPs (Figure 1) were selected using Haploview (Barrett, Fry, Maller, & Daly, 2005) (aggressive tagging 2-marker haplotype r2≥0.8) and the HapMap CEU population SNP database (http://www.hapmap.org, Release 22/Phase II). These tSNPs accounted for greater than 90% of the variance of all HapMap SNPs (minor allele frequencies ≥5%) within the genomic region surrounding CNR1 Exons 3 and 4. The 12 tSNPs span approximately 18.7kb at Chromosome 6q14-q15 (Mean distance between tSNPs=1.70kb; Median=1.49kb). To genotype study participants, DNA was prepared by high-salt extraction from whole blood (Lahiri & Nurnberger, 1991) and assayed using Illumina Infininum II array BeadChips which were designed, manufactured and completed by Illumina (San Diego, CA). Genotype call rates were 100% for each of the 12 CNR1 tSNPs. Illumina utilizes their proprietary GenCall data analysis software to ascertain quality and reliability of the genotypes called. A 10% GenCall score (i.e. the 10th percentile rank for all GenCall scores of the study samples at a given locus) greater
