The present results are interesting in light of a study in human post-mortem brain tissue of ~12,000 ranked genes according to robustness of circadian rhythmicity across six brain regions; the top ranked circadian genes in that study were ARNTL, PER2, PER3 and NR1D1 and dysregulation in MDD vs controls were observed in these genes22. The gene discussed is NR1D1; the disease is major depressive disorder.