Researchers shed new light on the genetic relationship between three mood disorders associated with depression--major depression and bipolar disorder types 1 and 2, in a new study in the journal Biological Psychiatry , published by Elsevier.
"The clearest findings are a genetic distinction between type 1 bipolar and type 2 bipolar, and the greater similarity of type 2 bipolar to major depressive disorder," said first author Jonathan Coleman, PhD, a statistical geneticist and postdoctoral fellow in the lab of senior author Gerome Breen, PhD at the Institute of Psychiatry, Neuroscience, and Psychology at Kings College London, UK.
Both types of bipolar disorder used to be referred to as 'manic-depressive disorder'. Mania is a behavioral state associated with behavioral activation, euphoric or irritable mood, reduced need for sleep, impulsive behavior, impaired judgement, racing disorganized thoughts, impulsive behaviors, and frequently strongly held false beliefs (delusions) or hallucinations. Bipolar disorder type 1 is associated with mania and depression, while bipolar 2 is predominately associated with depression marked by mild symptoms reminiscent of mania, called hypomania.
The insights came from several extremely large datasets analyzed together. For their meta-analysis, Coleman, Breen and their co-authors combined genome-wide association studies from three large datasets of people with major depression and bipolar disorder to evaluate shared and distinct molecular genetic associations. Most of the data came from the large international Psychiatric Genomics Consortium. Additional data came from the UK Biobank, a major health resource established by the Wellcome Trust, and the online genetic service platform, 23andMe.
There are significant racial and ethnic differences in the findings from genome-wide association studies (GWAS). The findings of this study pertain only to people of European ancestry and findings might be different in other groups. Related Stories
Also in Industry News
How to decide whether or not to start treatment for prostate cancer?
Analysis of the SARS-CoV-2 proteome via visual tools
$65m investment increases British Patient Capital’s exposure to life sciences and health technology