DCC and major depressive disorder: These genes include FYCO1, CXCR6, SLC6A20, CRHR1, RP11-105 N13.4, DCC, RP1-71H24.1, OAS3, NR1H2, NAPSA, IFNAR2, AP000295.9, CTB-191 K22.6, FLT1P1, NSF, ZSCAN31, RP5-874C20.6, RP5-874C20.3, ZKSCAN4, LINC00649, NKAPL, PGBD1, Wnt3, ACTR3P3, GRM5. Most of them have already been demonstrated to be novel risk factors for COVID-19 and/or MDD.