Table 1. Summary statistics for significant markers.

Minor allele frequencies, odds ratios, and population attributable fractions were calculated for all SNPs using both data from AlzGene.org and the Cache County population-based study. Population attributable fractions are reported as percentages. For better interpretation and comparison to previous studies, the risk allele for each locus (whether the major or the minor allele) was used to calculate population attributable fractions but the minor allele was used for odds ratios. Minor allele frequencies are comparable between AlzGene.org and the Cache County data. Odds ratios are generally similar except ABCA7 and CR1 differ in direction. Individual population attributable fractions in Cache County varied in magnitude when compared to those calculated for AlzGene.org. Combined population attributable fractions were also lower in Cache County. As expected APOE ε4 and APOE ε2 have strong population effects whereas the remaining alleles have minimal individual effect. Based on AlzGene.org data, combined population attributable fractions suggest the combined effect of the nine non-APOE alleles is approximately equal to APOE ε2 or APOE ε4 alone; however, the nine non-APOE alleles appear to have a larger effect than either APOE allele in the Cache County data.