FEASS[Twins]

It is known that the epigenome of sperm cells can be changed when men are exposed to lifestyle changes, such as increased exercise or weight loss. Further, these epigenetic changes have been noted to occur at places on the DNA that may impact the health and development of their children. One lifestyle choice of which we are still working to understand the impact on the quality and epigenome of sperm is diet . Previous research in animals has shown that certain diets in fathers-to-be can potentially lead to altered health outcomes in their children. To help us better understand how the current modern diets of men may be effecting their sperm we designed the Food intake and Epigenetic Alteration in Spermatozoa of Singletons and Twins, also known as the FEASST study. This is the Twins arm of the study where the participants are monozygotic and dizygotic twins, giving us the unique opportunity to examine epigenomes after diet changes in men who have identical or very similar DNA sequences.

We will recruit twin male pairs to participate in our study and provide each of the twins to a different specific diet, and we will collect health information and biological samples such as blood, semen, and saliva throughout. The diets will consist of a ‘Processed’ and ‘Unprocessed’ version. The aim of these two diets is to study the health effect of consuming a diet matching what men are supposed to eat versus what they are actually eating. The ‘Processed’ diet is based on the average food intake of American men, and is made to represent what men of child-rearing age are presently eating, and consists of food products that have undergone industrial processing with added sugar, enriched in saturated fat, cholesterol, and sodium.  The ‘Unprocessed’ diet is based on the Australian Dietary guidelines and is rich in typically healthy food products such as fruits, vegetables, whole grains, unsaturated fats, lean protein, and fibre.

For three weeks, one twin will be given the ‘Processed’ diet, while the other twin is given the ‘Unprocessed’ diet. Throughout the three weeks, various physiological measurements are taken such as: body weight, sperm quality, blood levels of markers related to reproduction and metabolism, and survey information surrounding mental and physical health.

Once all of the participant samples have been collected, laboratory-based experimentation will take place to determine variations in the health, content, and genetic programming of the sperm. We will explore characteristics of the sperm epigenome that are involved in turning gene expression up or down including marks on the DNA, how the DNA is organised or packaged, and the presence of other molecules which interact with DNA. We will analyse data from these experiments to determine the relationship between differential dietary intake in men with identical DNA on the health and epigenetic characteristics of the sperm.