Skip to main content
KBS_Icon_questionmark link-ico

Gender differences in prenatal brain development

Female and male brains develop differently in the womb because of changes to how their DNA is read, according to researchers from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) and the University of Exeter, published in Genome Research.

The study identified a number of gender differences in the process called DNA methylation that determines how genes are activated in the fetus and so directs the way brain cells develop. Methylation of DNA is used as a “switch” that regulates the expression of genes in a process known as epigenetics and this gene expression could potentially contribute to brain differences that affect behaviour, brain function and disease associated with gender. 

“Males and females show differences in their susceptibility to some neurological conditions,” said Helen Spiers of the Department of Social Genetic & Developmental Psychiatry, IoPPN, and first author on the study. “For example, autism affects five males to every female. Understanding sex differences in brain development may help us understand the origins of these differences.”

Using cutting-edge technology, the researchers measured genome-wide patterns of DNA methylation in nearly 200 samples, spanning 23 to 184 days after conception. Significant changes in DNA methylation across brain development were found at more than 7% of the 400,000 genomic sites assessed.

“The prenatal period is a time of dramatic plasticity, when the brain is laying down the structures that control neurobiological function across life,” said Professor Jonathan Mill, of the University of Exeter Medical School and the IoPPN, who led the study. “Understanding the way in which genes are activated during this important period in the brain could teach us about the origins of disorders with a neurodevelopmental component, such as autism and schizophrenia.”

Notes to editors

Paper reference: Spiers, H. et al. ‘Methylomic trajectories across human fetal brain development’ published in Genome Research DOI:

Image: the painting depicts an ultrasound scan of a human fetus at twelve weeks old. The image is deliberately abstracted to provide an impression of incompletion, reflecting the ongoing process of brain development during this dynamic period. The illustration, by Helen Spiers, features on the cover of Genome Research's March issue.

For further information contact Tom Bragg, Press Officer at IoPPN, King’s College London, on +44(0)2078485377 or email