http://medicalxpress.com/ en-us Medical Xpress internet news portal provides the latest news on Health and Medicine. Many of the body's processes follow a natural daily rhythm or so-called circadian clock. There are certain times of the day when a person is most alert, when blood pressure is highest, and when the heart is most efficient. Several rare gene mutations have been found that can adjust this clock in humans, responsible for entire families in which people wake up at 3 a.m. or 4 a.m. and cannot stay up much after 8 at night. Now new research has, for the first time, identified a common gene variant that affects virtually the entire population, and which is responsible for up to an hour a day of your tendency to be an early riser or night owl. http://medicalxpress.com/news/2012-11-gene-distinguishes-early-birds-night.html Genetics Fri, 16 Nov 2012 11:34:27 EST news272288055 Perelman School of Medicine at the University of Pennsylvania researchers have discovered a mechanism involving the neurotransmitter dopamine that switches fruit fly behavior from being active during the day (diurnal) to nocturnal. This change parallels a human disorder in which increased agitation occurs in the evening hours near sunset and may also be due to higher than normal dopamine levels in the brain. Sundown syndrome occurs in older people with dementia or cognitive impairment. http://medicalxpress.com/news/2012-05-sundown-syndrome-like-symptoms-fruit-flies.html Genetics Mon, 14 May 2012 09:39:09 EST news256207143 A study by researchers at Brigham and Women's Hospital (BWH) reinforces the finding that too little sleep or sleep patterns that are inconsistent with our body's "internal biological clock" may lead to increased risk of diabetes and obesity. This finding has been seen in short-term lab studies and when observing human subjects via epidemiological studies. However, unlike epidemiological studies, this new study provides support by examining humans in a controlled lab environment over a prolonged period, and altering the timing of sleep, mimicking shift work or recurrent jet lag. http://medicalxpress.com/news/2012-04-disrupted-internal-clock-higher-diabetes.html Health Wed, 11 Apr 2012 14:00:01 EST news253366537