Schizophrenia and Bipolar Disorder Share Genetic Causation
Schizophrenia and bipolar disorder have a common genetic etiology, ie genetic causation share, according to an article published by UK medical journal The Lancet.
A team of scientists from the Karolinska Institute in Stockholm has reached this conclusion after analyzing over thirty years to nine million people belonging to two million families.
Of the nine million 35 985 40 487 persons suffering from schizophrenia and bipolar disorder.
The researchers measured the risk of first-degree relatives of affected-parents, children, siblings and siblings-for schizophrenia, bipolar disorder or both diseases (comorbidity).
Speaking to EFE, the head of the investigation, Paul Lichtenstein, said that relatives of patients with schizophrenia had increased risk of bipolar disorder than the general population.
In addition, relatives of those affected by bipolar disorder had a higher risk of developing schizophrenia than the general population.
This finding sheds some light on the medical debate created around the question of whether both diseases are the clinical outcome of different processes or whether, instead, are the result of shared processes.
The brothers of the patients had a probability of developing schizophrenia nine times greater than that of the general population and eight times more likely to suffer from bipolar disorder.
The mother's brothers had 3.6 times more likely to have schizophrenia and 4.5 times higher of having bipolar disorder.
As for the brothers of a father, your chance of developing schizophrenia was 2.7 times that of the general population, and of having bipolar disorder was 2.4 times higher.
The heritability, ie the proportion of a genetically inherited trait and not learned or acquired by the influence of the environment, was 64 percent in cases of schizophrenia and 59 percent for bipolar disorder.
For its part, the genetic causes of morbidity were 63 percent of cases.
Lichtenstein said that although his team failed to carry out an analysis of the chromosomes, the results indicate that bipolar disorder and schizophrenia have to share regions of genes.
“The same groups of genes confer susceptibility to various psychiatric problems,” he told Efe.
“In clinical practice, the structure underlying psychosis and knowledge of the common causes of these disorders can be beneficial to the choice between different treatment options and drug development,” he said.
