Our study used multiple highly correlated SNPs to represent each of the 4 tested loci, depending on availability in each dataset, and all subjects were of European ancestry. Hence this study is not designed to determine which SNP(s), among the highly correlated SNPs for each locus, are most likely to be biologically involved. Future work, involving large-scale meta-analysis of other populations (e.g. Asian or African ancestry) to capitalize on LD differences between populations, comprehensive functional annotation of genetic variants, DNA re-sequencing and variant discovery, and functional and animal studies may help narrow down these large sets of correlated SNPs to the most promising causal alleles.
