All these theories have their proponents and opponents – for scientists are certainly far from reaching an agreement about the biological causes of sleep. He has found that the expression of the gene FABP7 changes over the day inside the brains of mice. This discovery raised the question of how humans might be affected by mutations in the FABP7 gene. So the team turned to a sleep study of 300 Japanese men that included analysis of their DNA. Crucially, a total of 29 of these men were found to have a special variant of the FABP7 gene: one that was correlated with their sleep patterns.

Source: The Guardian April 09, 2017 06:00 UTC