How age and sex influence our body clocks

(Image: Pixabay CC0) Researchers have uncovered the intricacies of gene expression rhythms in humans, shedding new light on how sex and age influence our body clocks. The human body runs on a finely tuned clock synchronized to the 24-hour cycle of Earth's rotation, known as the circadian clock, which controls various physiological processes such as the sleep-wake cycle, hormone production, and metabolism. In a new study, researchers led by Felix Naef at EPFL were able to uncover the organization of tissue-specific gene expression rhythms in humans, and shed light on how our body clocks depend on sex and age. In model organisms, analyzing molecular rhythms is usually done using time-stamped measurements - but such data are not readily available in humans. To work around this, the researchers used existing measurements from a large cohort of post-mortem donors, combined with a novel computer algorithm that was designed to assign internal clock times to nearly one thousand donors. "Interestingly, the data-science algorithm we developed turned out to resemble models from magnetic systems, which are well studied in statistical physics," says Felix Naef. Using this innovative approach, the researchers obtained the first comprehensive and accurate whole-organism view of 24-hour gene expression rhythms in 46 human tissues.