The most complete analysis, a meta analysis that included both COGA and S4S, did not produce any genome-wide significant results. Additionally, none of the signals from the within COGA meta analysis replicated. Only one SNP from the within COGA meta analysis was located in a gene (PKD1L2 on chromosome 16) with prior evidence of association with externalizing problems (Anney et al., 2008). It is possible the failure of this SNP to replicate in the combined sample meta analysis was a lack of statistical power. It is also possible that some or all of the associations from the within COGA meta analysis were false positives.
