The Gene for Zzzzzzzz
9 November 2010
The genetics of sleep. DNA may determine why some individuals sleep longer than others.
Many of us are zombies without 8 hours of sleep, while envied others seem to get by just fine on much less. Now geneticists have found the first gene in the general population that seems to influence how much sleep we need.
Sleep interests biologists in part because it varies with other factors, such as weight, that make people more prone to diabetes or heart disease. (The larger a person's body mass index, the less they generally sleep.) In search of sleep genes, a group of European researchers studied populations in seven countries, from Estonia to Italy, for a total of 4260 subjects. Each one filled out a simple questionnaire asking about his or her sleep habits and donated a DNA sample. The researchers then scanned the participants' DNA for thousands of genetic markers, looking for ones that were more common in people who slept more than those who slept less.
Sleep duration correlated strongly with a single genetic marker in a gene called ABCC9.
The ABCC9 gene codes for a protein called SUR2 that is part of a potassium channel, a structure that funnels potassium ions into and out of cells.
ABCC9 is the first gene with such a strong association with sleep duration detected in the general population. Allebrandt says that because the SUR2 protein is also involved in heart disease and diabetes, the finding that it impacts sleep should also interest researchers working on those diseases.