Schizophrenia is a severe and complex mental illness that affects about 1% of the population. Diagnosis currently relies on subjective clinical interviews and the assessment of ambiguous symptoms which frequently lead to delays in diagnosis and treatment. A physical method of diagnosing the condition would, therefore, be very useful. Researchers at Cambridge University looked to find a 'protein fingerprint' in the blood by comparing samples from those with and without schizophrenia. They found that those people with schizophrenia had raised levels of substances called alpha defensins which kill microbes and viruses as part of the immune system. The higher levels of alpha defensins were found in people who had recently been diagnosed with schizophrenia suggesting that this was not due to the drugs used to treat the condition or the disease itself. Unaffected twins of people with schizophrenia also had higher alpha defensin levels leading the researchers to speculate that this might point to a genetic link to the condition.
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