The following is an excerpt.
Genes believed to regulate sleep rhythm are expressed abnormally in people with major depressive disorders, scientists say. The study is one of the first in humans to provide direct evidence of a disturbed circadian rhythm in people with depression.
Symptoms of depression can include sleep disturbance, with difficulties in falling asleep at night or feeling fatigued during the day, but the precise mechanism for this remains unknown. Although the circadian rhythm – the 24-hour cycle in living beings – has been observed in gene expression in animal studies, its presence in the human brain has been difficult to confirm
Read the full story here: Body clock genes linked to depression