To eliminate concerns about potential false-positive results, especially for studies reported in earlier years, we focused primarily on the genes showing significance in at least two independent studies with a sample size of ≥ 1,000 or within (or close to) nominated linkage regions or overlapping with GWAS results but with a sample size of ≥ 500 based on the statistical thresholds set by each study. Because the reported sex-average recombination rate is 1.30 ± 0.80 cM/Mbp,39 in this report, we defined candidate genes within 2 megabase pairs (Mbp) of any linkage region as “within” and 2–5 Mbp as “close to.” The sample size requirement was determined with the following parameters: two-tailed α = 0.05, population risk = 0.30, minor allele frequencies = 0.20, and genotypic relative risk = 1.3 with an approximate odds ratio (OR) of 1.5 or 0.7, which is similar to the statistics usually found in candidate gene association studies. For a statistical power of 0.80 (β = 0.20) using the allelic test, the minimum sample size for a case-control study is 1,062, with equal numbers of cases
