Five Major Mental Disorders Share Common Genetic FactorsMajor mental disorders traditionally thought to be distinct share certain genetic glitches, according to a new study.
Scientists have long recognized that many psychiatric disorders tend to run in families, suggesting potential genetic roots. Such disorders include autism, attention deficit hyperactivity disorder (ADHD), bipolar disorder, major depression, and schizophrenia. Symptoms can overlap and so distinguishing among these five major psychiatric syndromes can be difficult.
Their shared symptoms suggest they may also share similarities at the biological level. In fact, recent studies have turned up limited evidence of shared genetic risk factors, such as for schizophrenia and bipolar disorder, autism and schizophrenia, and depression and bipolar disorder.
To take a broader look, an international research consortium conducted an analysis that incorporated data from genome-wide association studies (GWAS) of the five major disorders. This type of study involves scanning through thousands of genetic markers in search of tiny variations that appear more often in people who have a particular condition than in those who don’t.
As reported online in the Feb. 28, 2013, Lancet, the scientists screened for evidence of illness-associated genetic variation among more than 33,000 patients. All had been diagnosed with at least one of the five disorders. A comparison group included about 28,000 people who had no major psychiatric diagnosis.
The analysis revealed variations significantly associated with all five disorders. These included variations in two genes that code for the cellular machinery that helps regulate the flow of calcium into neurons.
Variation in one of these, called CACNA1C, had previously been linked to bipolar disorder, schizophrenia, and major depression. CACNA1C is known to affect brain circuitry involved in emotion, thinking, attention, and memory—functions that can be disrupted in mental illnesses. Variation in another calcium channel gene, called CACNB2, was also linked to the five disorders.
In addition, the researchers discovered illness-linked variation for all five disorders in certain regions of chromosomes 3 and 10. Each of these sites spans several genes, and causal factors haven’t yet been pinpointed. The suspect region along chromosome 3 had the strongest links to the disorders. This region also harbors certain variations previously linked to bipolar disorder and schizophrenia.
“Although statistically significant, each of these genetic associations individually can account for only a small amount of risk for mental illness,” says study co-author Jordan Smoller, MD, ScD, of Massachusetts General Hospital.
Because of this, the variations couldn’t yet be used to predict or diagnose specific conditions. But these results may help researchers move closer to making more accurate diagnoses. They may also help lead to a better understanding of the factors that cause these major mental disorders.
Community-Based Programs Improve the Lives of Young Adults With Mental Health ChallengesYoung adults (ages 18–25) taking part in community-based treatment programs achieve positive outcomes in behavioral and emotional health, daily life skills, employment, enrollment in school, and reduced homelessness, according to a new report from the Substance Abuse and Mental Health Services Administration (SAMHSA). In addition, older adolescents and young adults who had participated in these treatment programs reported lower levels of substance-use disorders, according to the report, which notes that 20 percent of young adults living in U.S. households had a mental health condition in the last year.
Among older adolescents and young adults participating in the SAMHSA-sponsored Comprehensive Community Mental Health Services for Children and Their Families Program, 28 percent showed significant improvement in their behavioral and emotional health within the first six months, and 38 percent showed significant improvement within the first year. Many participants reported they had greater confidence in their abilities to perform important life skills such as preparing meals and securing rental agreements. Homelessness dropped by 36 percent after six months in services among those ages 18 and older participating in the program.
The report also shows that many participants in SAMHSA- sponsored substance-use treatment programs were also treated for mental conditions and that this treatment had a beneficial effect in terms of mental well-being and recovery from substance-use disorders. Among those older adolescents and young adults who participated in these programs, there was a 34 percent decrease in the number of young adults who reported experiencing mental health concerns such as depression or anxiety, and an 80 percent increase in the number of young adults who were living in the community.
In addition, in SAMHSA’s Pregnant and Postpartum Women program, 86 percent of participating young adults reported no substance use after six months of treatment (versus only 40 percent of those entering the program), and 29 percent reported being employed or in school (versus only 13 percent of those entering the program).
Source: Download “Promoting Recovery and Independence for Older Adolescents and Young Adults Who Experience Serious Mental Health Challenges” and view the full list of field references. Read the press release.