CDH18 and major depressive disorder: While the reference minor alleles of SNPs rs6537837 and rs242939 (mapping the GNAI3 and CRHR1 genes, respectively) were reported as protective markers for depression, the reference minor alleles for the rs349475, rs310501, and rs1800532 (mapping the genes LINC02223;CDH18, VCAN;HAPLN1, and TPH1) were identified as risk markers for depression.