Multiple diagnoses are the norm with mental illness; new study helps explain why
More than half of people diagnosed with one psychiatric disorder will be diagnosed with a second or third. About one third have four or more.
A sweeping new genetic analysis helps explain why: Subsets of disorders share many underlying genes.
The researchers analyzed data from hundreds of thousands of people who submitted genetic material to large-scale datasets. When they looked at genes associated with 11 disorders, clear patterns emerged:
About 70% of the genetic signal associated with schizophrenia is also associated with bipolar disorder; there is large genetic overlap between anxiety disorder and major depressive disorder; and anorexia nervosa and obsessive-compulsive disorder share similar underlying genes.
The finding could open the door to treatments that address multiple psychiatric disorders and help reshape the way diagnoses are given.
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Principal investigator
Andrew Grotzinger
Funding
National Institute of Mental Health (NIMH)
Collaboration + support
Psychiatric Genetics Consortium; iPSYCH; UK Biobank; 23 and Me; University of Texas at Austin
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Multiple diagnoses are the norm with mental illness; new genetic study explains why