A new population-based study led by CHU Sainte-Justine researcher and Université de Montréal medical professor Tomas Paus reveals the roles of maternal and fetal genes in the growth of a baby’s cerebral cortex.
Published last week in Nature Communication, the study shows that genetic variants associated with higher birth weight are also associated with greater growth of the cerebral cortex.
However, food abundance or scarcity seems to influence the extent of the role played by the genes of the mother and the unborn baby.
With postdoctoral fellow Daniel Vosberg, Paus analyzed birth weight, birthweight genes and brain magnetic resonance imaging (MRI) data from several thousand adults in the UK Biobank, a biomedical database in the United Kingdom.
These analyses confirmed that higher birth weight is associated with larger cortex size (measured by surface area). In addition, the genetic variants present in the mother and baby that are associated with birthweight are also associated with cortical surface. In the baby, genes associated with insulin action are decisive, while in the mother, genetic variants favouring toxin elimination at the cellular level play a major role.
The two groups of genetic variants are not always equally important in determining cortex size.
“By comparing data by birth year and using statistical modelling and cellular interaction analysis, we’ve demonstrated the role of exposure to food restriction during gestation or infancy,” said Paus.
