Imaging genetics provides an opportunity to distinguish associations between genetic variants and brain imaging phenotypes. Historically, the main focus was on adults and adolescents but, very few studies have focused on brain development in infancy and early childhood. This is a crucial knowledge gap because developmental changes in the brain during the prenatal and early postnatal periods are controlled by dynamic gene expression patterns that play a significant role in establishing an individual’s risk for later psychiatric disease and neurodevelopmental disabilities.
Early neurodevelopment is a sensitive time for accumulating transdiagnostic risk for psychiatric diseases. In the human brain, neurodevelopment begins about 2 weeks after conception. Genetic effects explain around 85% of the variance in white matter volume and 56% of the variance in gray matter volume at around 1 month of age. The variants associated with psychiatric disorders influence early neurodevelopment, both independently and through interaction with environmental factors
