The role of sleep problems and circadian clock genes in childhood psychiatric disorders.

CLOCK gene research and the analysis of circadian rhythmicity on the behavioural, cellular and molecular level are increasingly contributing to accumulate clinically relevant knowledge in the fields of neuroscience, psychopharmacology and adult psychiatry. However, the role of circadian phenomena, including sleep alterations in mental disorders during childhood and adolescence remains largely enigmatic. Fortunately, recent publications have addressed this problem and there is now some evidence available highlighting the relevance of CLOCK genes in conditions, such as ADHD, mood disorders, schizophrenia and anxiety disorders.