The thought of developing bipolar disorder seemingly out of nowhere can be scary. Also known as manic-depressive illness, the disease can be severe and life-changing. Drastic changes in mood, including lows that leave you unable to function and highs that remove you from reality, can make it nearly impossible to make it through a daily job or routine.
Scientists have known for some time that certain genes are likely to cause bipolar disorder, and some of these genes are also linked to an increased risk of schizophrenia and alcoholism. But the things behind the development of bipolar disorder are likely a mix of different factors, ranging from gene mutations to a person’s upbringing, as well as that person’s penchant for anxiety and other mental health issues.
The first thing that comes to mind when scientists discuss bipolar disorder is its tie to certain genes that may cause it. These genes tend to run in families, increasing the risk for a bipolar person’s relatives to also eventually get the disease.
But all the genes that might go into bipolar disorder still aren’t fully known. According to a new study published in Proceedings of the National Academy of Sciences, the accumulation of certain rare versions of genes might have something to do with the disease. The researchers sequenced the genomes of 200 people from 41 different families that had a history of bipolar disorder, and identified 164 rare forms of genes that were more likely to appear in people with the disease. Bipolar people had six of these rare forms on average, while their healthy counterparts averaged about one. These genes in question are involved in the monitoring of ions to enter or leave neurons in the brain, which in turn affects how neurons pass information through the brain.
“There are many different variants in many different genes that contribute to the genetic risk,” Jared Roach, a geneticist at the Institute for Systems Biology in Seattle and an author of the study, said. “We think that most people with bipolar disorder will have inherited several of these… risk variants.”