Study identifies DNA Methylation markers linked to schizophrenia risk in newborns

A team of international researchers, led by Virginia Commonwealth University, has discovered markers that could indicate an individual's susceptibility to schizophrenia early in life. 

Schizophrenia is a severe psychiatric disorder that typically emerges in young adulthood and affects approximately 1% of the global population. Individuals with the condition are up to three times more likely to die early, and often face discrimination, social isolation, and physical illness. 

Detecting the risk of developing schizophrenia early could enable interventions that minimise the impact of the disease on individuals, families, and communities. The findings have been published in Molecular Psychiatry.

Schizophrenia has a genetic component, but environmental factors also play a role in its development. Methylation, a process that alters the expression of genes by regulating which are turned on or off, can be triggered by environmental factors. 

However, it is challenging to study genetic triggers for schizophrenia because methylation changes can be caused by the disease itself and related factors, such as stress and medication. Additionally, because schizophrenia is a brain disorder, obtaining samples before the onset of the disease is impossible.

To address this challenge, the research team used a unique approach. They analysed blood samples taken shortly after birth from 333 infants in Sweden, tracking 24 million methylation marks. 

The team used statistical analysis to study methylation marks on a cell-type-specific level. Since the samples were collected before the onset of the disease, the findings could not be influenced by schizophrenia or other postnatal factors.

The team validated their findings from the blood samples by comparing them to transcriptional data from 595 postmortem brain samples from different individuals, some with schizophrenia and others in a control group without the disease. The brain samples were provided by investigators from around the world. 

The team also compared their findings against methylation data from adult blood drawn from schizophrenia cases and controls, totalling 2,970 individuals.

The researchers discovered that certain differences in methylation present in newborns indicate an increased risk of developing schizophrenia. The methylation differences identified are unique to specific cell types in neonatal blood. The team hopes to continue researching these methylation differences to develop clinical biomarkers that will enable early detection and intervention.