Genetic Imprints in the Brain
Neuroscientist Anthony Isles studies how the epigenetic phenomenon of genomic imprinting influences the brain and its functions.
As an undergraduate student, Anthony Isles, now a neuroscientist at Cardiff University, was fascinated by the study of behavior and genetics. When applying for graduate programs, he accidentally landed an interview for a different graduate program at the University of Cambridge than the one he had originally considered. This fortuitous event set him on a journey to understand how the epigenetic phenomenon of genomic imprinting affects the brain.
What is genomic imprinting?
The concept of genomic imprinting emerged about 40 years ago. At that time, embryologists wanted to understand whether the DNA we inherit from each of our parents is functionally equivalent. To do this, they created diploid embryos that had two copies of either maternal or paternal DNA. They found that these embryos did not survive mid-gestation, suggesting that there is a distinction between the maternal and paternal genomes. They called the phenomenon in which some genes are expressed only from the maternal copy while others are expressed only from the paternal copy genomic imprinting. Over the past 20 years, researchers have identified a number of imprinted genes and the epigenetic mechanisms—DNA methylation, histone modification, and noncoding RNA—that make their expression parent dependent.
How do imprinted genes affect the brain and behavior?
The concept that genomic imprinting is important for parenting, defined as social behaviors that help the offspring survive and develop optimally, emerged in the late 1990s.1 However, researchers haven’t explicitly tested whether imprinted genes are more likely to affect parenting. In a recent study, we looked at publicly available transcriptomic data from a known hypothalamic region involved in parenting in mice. We found that imprinted genes are enriched in this area, supporting the idea that they are essential for parental care. We then induced changes in maternal and paternal parental behavior by knocking out one of these genes and observed deficits in parental behavior, revealing a functional link.2
This interview has been condensed and edited for clarity.
- John RM, et al. Nat Rev Genet. 2023;24(11):783-796.
- Higgs MJ, et al. PLoS Genet. 2023;19(10):e1010961.