06 Dec Epigenetics Affecting Sperm May Explain Why Children of Obese Fathers Are Prone to Obesity
MedicalResearch.com Interview with:
Ida Donkin MD, PhD
Postdoc, Medical Doctor, PhD
University of Copenhagen
Faculty Of Health Sciences
Medical Research: What is the background for this study?
Dr. Donkin: We know that children of obese fathers are more prone to develop obesity themselves – regardless of the weight of the mother. We also know that obesity and diabetes are diseases with a very big inheritable components in their aetiology. If your parents are obese, you have a risk of about 75% percent of developing obesity yourself. But we do not know how the disease is inherited from one generation to the next. Despite exhaustive research trying to investigate genes potentially responsible for this, and more than 125 genetic mutations have been discovered to associate to the development of obesity, all the genetic mutations put together cannot explain more than about 10% of the actual inheritance. So how is obesity inherited from parents to children? One explanation could be the transfer of epigenetic information from one generation to the next. Epigenetic information is established in our body’s cells in response to our lifestyle and the environment around us. We discovered that the epigenetic factors of semen cells also responds to changes in our lifestyle, and we speculated whether these might be the key to understand how obesity in dads can lead to obesity in children.
Medical Research: What are the main findings?
Dr. Donkin: In this study we discovered that the information kept in our semen cells responds dynamically to changes in our lifestyle. If you are obese, your semen cells will contain a different epigenetic pattern than if you are lean. Weight loss induced by gastric bypass surgery will dynamically change these epigenetic patterns, meaning that by changing our lifestyle, we can actively change the epigenetic information we pass on to our children. Other research groups have created solid evidence showing us that most these epigenetic marks kept in the sperm cells will be passed on to the embryo at fertilization. The epigenetic information can affect the development of the embryo, and thereby change the health – and the risk of disease – of our children. Our study thus provides a likely explanation for the mechanism of the inheritance of acquired traits and diseases through generations, and gives us a likely explanation as to why children of obese fathers are more prone to develop obesity themselves.
Medical Research: What should clinicians and patients take away from your report?
Dr. Donkin: We still need to investigate, if thee changed epigenetic patterns in our semen cells will actively change the health and risk of disease of our children. Research tells us it is so in aniamls, but this has not been proven for humans yet. If this is so, we should be more careful of our pre-conceptional behavior in order to diminish risk of disease in our children. We have known for long that the lifestyle of the pregnant mother can affect the health of her child, but this finding tells us that father’s lifestyle might affect the child’s health as well. Clinicians should advice parents-to-be to eat healthy, loose weight if obese, and exercise regularly in the time before they plan to conceive their children. Hopefully, in the long run, an increased public awareness of the impact of our pre-conceptional behavior can help us prevent inheritance of especially metabolic disorders such as obesity and type 2 diabetes, as well as other diseases that have a great part of non-genetic inheritance in their aetiology.
Medical Research: What recommendations do you have for future research as a result of this study
Dr. Donkin: It is important to investigate if these changed epigenetic patterns in sperm of obese men will indeed impact the health of their children. And if so, it will be interesting to figure out exactly how these marks are established in the semen cells, when they are established, and if we can do anything to erase them. Moreover, we need to investigate what other aspects of our lifestyle that may affect our children’s health, to be able to generate more specific advises for parents-to-be in order to improve the health of our future generations. It would moreover be interesting to know if the mother’s pre-conceptional behavior may affect our children as well, or if it os only her behavior during pregnancy that counts.
Donkin and Versteyhe et a. Obesity and Bariatric Surgery Drive Epigenetic Variation of Spermatozoa in Humans. Cell Metabolism, December 2015 DOI: 10.1016/j.cmet.2015.11.004
Ida Donkin MD, PhD (2015). Epigenetics Affecting Sperm May Explain Why Children of Obese Fathers Are Prone to Obesity