A simple cheek swab could one day provide a quick and noninvasive diagnostic test for schizophrenia. A new study published in Science Advances has identified higher levels of two biological markers in the cheek swabs of patients with schizophrenia compared with people who don’t have this mental health disorder. Schizophrenia is a long-term condition with a range of symptoms including hallucinations, delusions, muddled thoughts and loss of interest in everyday activities.

There is no single test for the illness, and diagnosis can be challenging because symptoms vary widely between people and typically relies on observing a patient’s behavior. It can, therefore, sometimes take months for a professional to make a diagnosis with any degree of certainty, as they have to rule out other possible causes. That is a lot of time for someone to wait without the right treatment if it is needed.

So researchers led by a team at Rutgers University in New Jersey decided to investigate whether molecular signatures in easy-to-collect buccal (cheek) cells could serve as reliable biomarkers.