# Genetic basis for bipolar disorder
**URL:** https://boards.straightdope.com/t/genetic-basis-for-bipolar-disorder/672615
**Category:** Miscellaneous and Personal Stuff I Must Share
**Created:** [October 30, 2013, 2:26am UTC](https://boards.straightdope.com/t/genetic-basis-for-bipolar-disorder/672615 "2013-10-30T02:26:57Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@deltasigma](https://boards.straightdope.com/u/deltasigma)
#### Post date: [October 30, 2013, 2:26am UTC](https://boards.straightdope.com/t/genetic-basis-for-bipolar-disorder/672615/1 "2013-10-30T02:26:57Z")
I don’t know if this is the first solid genetic lead, but this sounds exciting. From the [NIH director’s blog](http://directorsblog.nih.gov/2013/10/29/basic-science-finds-new-clue-to-bipolar-disorder/):
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> We know that heredity, along with environment, plays an important role in many mental illnesses. For example, studies have revealed that if one identical twin has bipolar disorder, the chance of the other being affected is about 60%. There are similar observations for autism, schizophrenia, and major depression. But finding the genes that predispose to these conditions has proven very tricky.
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> Now, an NIH-funded team at Baylor College of Medicine has demonstrated for the first time that extra copies of a gene that codes for a protein called Shank3 can cause manic episodes similar to those seen in some types of bipolar disorder [1]. The researchers initially tested their hypothesis in mice and then, building upon those findings, went on to find extra copies of the \*SHANK3 \*gene in two human patients—one with seizures and attention deficit hyperactivity disorder and another with seizures and bipolar disorder.
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> The researchers then explored how extra amounts of Shank3 protein wreak havoc inside the brain. In lab studies that examined brain cells, called neurons, derived from the Shank3 mice, the researchers found that higher-than-normal levels of Shank3 boosted the number of dendritic spines on the neurons. That’s a key finding, because dendritic spines are structures that neurons use to receive excitatory signals.
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### Author:  [@monstro](https://boards.straightdope.com/u/monstro)
#### Post date: [October 30, 2013, 3:01am UTC](https://boards.straightdope.com/t/genetic-basis-for-bipolar-disorder/672615/2 "2013-10-30T03:01:47Z")
I googled “Shank3”. Apparently abnormalities with this gene are also associated with ADHD, autism, OCD, and Tourette’s, and schizophrenia.