XIRP2 and major depressive disorder: By comparing the results of the present study with those of our previous WES study combined with structural neuroimaging analysis in patients with MDD [32], we discovered several genes that were not identified in previous studies, such as XIRP2, MUC5B, FRMPD3, and MUC6. Furthermore, a previous study found a significant association between one SNP (rs11592462) of CDH23 and thinning of the right anterior cingulate cortex, whereas the present study did not find any association between CDH23 and DTI parameters.