You are what your parents ate: A Darwinian perspective on the inheritance of food effects

• Darwin believed that food was probably the most powerful cause of variability – the fountainhead of evolution.
• Darwin explained the inherited food effects by his Pangenesis – a unifying theory of heredity and variation.
• There is accumulating evidence that parental diets influence the health and disease of subsequent generations.
• Two major underlying mechanisms are DNA methylation and RNA-mediated inheritance.
• A comparison of Darwin's gemmules with circulating DNA and mobile RNAs reveals intriguing similarities.

Darwin's theory of evolution by natural selection is based on a sound understanding of the causes of variability and the mechanism of inheritance. Of all the causes which induce variability, Darwin believed that food was probably the most powerful. He not only held that the amount and nature of food could affect the characters of the future offspring through the reproductive system, but also accounted for the inheritance of such environmentally induced variations by his Pangenesis hypothesis. He proposed that cells could “throw off” numerous, minute molecules called gemmules, which were capable of diffusion from cell to cell, circulation throughout the body, modification by changed conditions of life (food, climate, etc.), aggregation in the reproductive organs, and transmission from parent to offspring. Now there is accumulating evidence that parental diets influence the health and disease of subsequent generations through epigenetic changes in germ cells. Two major underlying mechanisms are DNA methylation and RNA-mediated inheritance. A comparison of Darwin's imaginary gemmules with circulating cell-free DNA and mobile RNAs reveals intriguing similarities. It will be a fascinating episode in the history of science if Darwin's Pangenesis should eventually be rediscovered.