Schizophrenia is a complex, potentially severe, and often misunderstood mental disorder. Patients are often unable to think or feel emotions normally and can have trouble distinguishing the reality from fantasy. Schizophrenia often takes months or years to develop and can contribute to alcoholism and substance abuse, social withdrawal, and self-harm or suicide. A patient’s average life expectancy is 12-15 years shorter than a normal adult and, unfortunately, even if the psychological symptoms can be kept under control social stigma often follows victims throughout their life.

Treatment is available and drugs known as antipsychotics are often effective in controlling the symptoms of schizophrenia, however, individual reactions can vary widely. Up to a third of patients show almost no improvement in their symptoms and some may abandon their medications when adverse drug reactions or side effects appear. The exact reasons why schizophrenia develops (and why treatment varies so widely) are still mostly unknown.  Environmental, developmental, and genetic factors are all thought to contribute.

In light of both increasing genetic research on schizophrenia and the rise of available pharmacogenetics, many new studies are investigating whether the variability in treatment effectiveness is also partly genetic. The neurotransmitters serotonin and dopamine can influence schizophrenia symptoms and are often the target of antipsychotic medicines; researchers have now identified some of the specific genes and enzymes that process and activate these chemicals.

For example, allele variability in the 5-HTT, HTR2A, DRD3, and engrailed1 gene families are now being compared to patient responses for the drugs haloperidol, risperidone, iloperidone, and clozapine. For the most part, identification still eludes us and many studies’ conclusions disagree with each other, but we do already know a few potentially important interactions. Furthermore, technological advances should open up new avenues of investigation. In particular, a method known as hypothesis-free genome-wide association studies (aka GWAS) may allow us to scan for thousands or millions of mutations across the human genome.

Schizophrenia is still an incredibly complex, often misunderstood disease. However, we are hopeful that individualized treatment can improve both the effectiveness of treatment and the quality of life for patients. Understanding the human brain and its associated disorders is one of the most daunting challenges of modern medicine.

A challenge we are excited to help tackle.

Sources: Reynolds G (2012), van Os J and Kapur S (2009), PubMed Health