Imagine constantly oscillating between feeling on top of the world and extremely low. Some days, you are impulsive with overflowing energy, while on other days, you are deeply depressed, lethargic, and devoid of energy.

Such abnormal mood swings are common for individuals with bipolar disorder.

The condition is largely genetic, meaning there is a congenital vulnerability to developing the disorder later in life.

"Bipolar disorder is one of the most heritable psychiatric disorders. Heritability is estimated to be around 80 percent, which is very high," says researcher Kevin O’Connell from the Centre for Precision Psychiatry at the University of Oslo.

"And yet, most of the underlying genes that increase the risk of the illness remain unknown," adds Professor and Centre leader Ole Andreassen, lead investigator of the study.

The most extensive study on bipolar disorder and genetics to date
Together with a large international research consortium, O’Connell and Andreassen conducted the most extensive study on bipolar disorder and genetics to date, involving over 2.9 million people. The findings were published in the prestigious journal Nature.

The researchers identified 298 genomic regions associated with bipolar disorder.

The study’s large scale and participant count increased the number of identified genomic regions nearly fourfold.

"267 of the 298 regions we found had not previously been linked to bipolar disorder," notes O’Connell.

The researchers further pinpointed 36 genes that play a crucial role in the condition's development.

Source: https://www.med.uio.no/klinmed/english/research/news-and-events/news/2025/the-genetic-key-to-bipolar-disorder.html