Tuesday, February 23, 2016

New Study Finds Gene that may be Linked to SAD

Seasonal Affective Disorder (SAD) is a disorder in which those suffering feel their mood begin to dampen during certain months of the year, usually the winter months. Those who suffer from the disorder do not simply feel sad when its cold out, the disorder is actually a form of depression that is brought on by the changing weather and daylight hours.

A team of researchers at the University of California, San Francisco may have found a gene that can be linked to SAD, something that has not been discovered before. The gene may also link disrupted sleep patterns, another ailment those suffering from SAD commonly have. The gene currently being studied is called PERIOD3 (PER3) and in order to test it, a mutated form was injected into mice who were then exposed to alternating light conditions. When their “days” were of a normal length, they behaved normally and when their “days” were shorter, they developed depression-like symptoms (“days” were controlled by the lighting in their environment).

This is significant due to the fact that studies have found mood may be affected by light but this is the first bit of genetic material to back that up.

Personally I view this as a win for those who suffer from SAD because I feel that it is often overlooked. I have a family member who was diagnosed with the disorder and actually undergoes light therapy during the winter because of this. While in most cases the disorder leads to minor forms of depression, it can also be very serious. Discovering a gene that may genetically prove the disorder exists in my opinion has the power to influence those who suffer from it to get help and those who brush it off to take it more seriously.


  1. Is PER3 also currently linked to forms of depression, or do they think that this is a gene connected only to SAD? I am interested to see where these studies lead due to the variety of problems that lead to what we typically think of as depression, and how they relate to SAD in particular.

  2. Before reading this post, I never even knew there was an actual disorder for people who get depressed when the seasons change. I wonder if the gene PER3 plays a role in people who are clinically depressed. Also, if it is involved in the development of depression, could scientists figure out a way prevent depression from occurring in the first place?