Prenatal nutrition, epigenetics and schizophrenia risk: can we test causal effects?

Area of Science:

• Neuroscience
• Genetics
• Nutritional Science

Background:

• Maternal prenatal nutrition is hypothesized to influence offspring schizophrenia risk via epigenetic mechanisms.
• Schizophrenia is associated with epigenetic changes, particularly DNA methylation in the brain.
• One-carbon metabolism is a potential mediator linking prenatal nutrition to schizophrenia risk.

Purpose of the Study:

• To explore the causal pathway between maternal prenatal nutrition and offspring schizophrenia risk.
• To investigate the mediating role of epigenetic factors, specifically one-carbon metabolism.
• To propose a novel methodological approach for strengthening causal inference in population studies.

Main Methods:

• Review of existing evidence linking prenatal nutrition, epigenetics, and schizophrenia.
• Focus on one-carbon metabolism as a key biological pathway.
• Proposal of a novel two-step Mendelian randomization approach to test causality.

Main Results:

• Existing studies suggest associations between prenatal nutrition, epigenetics, and schizophrenia.
• Post-mortem studies show DNA methylation changes in schizophrenia brains, but causality is not established.
• The proposed Mendelian randomization approach offers a way to test causal links.

Conclusions:

• Epigenetic effects mediated by one-carbon metabolism represent a plausible pathway linking maternal prenatal nutrition to offspring schizophrenia risk.
• The proposed Mendelian randomization methodology can enhance causal inference for epigenetic mediation in population studies.
• This approach can be broadly applied to investigate other exposure-health outcome relationships involving epigenetic factors.