WIKIMEDIA, PEDRO SIMOESIn the depths of February, many people living in wintry northern climes find themselves bummed out and craving the sunny days of summer. Now, researchers at the University of California, San Francisco (UCSF), have identified a gene that may underlie seasonal affective disorder (SAD), an affliction that strikes 10 percent of people who live at extreme northern or southern latitudes. What’s more, the gene may link disrupted sleep patterns—which SAD sufferers commonly experience—to mood shifts that often come with missing out on a solid night’s sleep. The work was published yesterday (February 22) in PNAS.
“This is the first human mutation directly linked to seasonal affective disorder, and the first clear sign of a mechanism that could link sleep to mood disorders,” study coauthor Louis Ptáček, a UCSF neurologist, said in a statement.
Researchers have been searching for molecular links between mood and the circadian clock for years. But Ptáček, UCSF’s Ying-Hu Fu, and a host of colleagues hit pay day when they found two rare variants of the PERIOD3 (PER3) gene in study participants who suffered both SAD and a sleep disruption disorder known as familial advanced sleep phase (FASP). People with FASP commence sleeping very early in the evening and wake up in the wee hours of the morning. “The identification of a mutation in PER3 with such ...
