A recent study, whose findings were documented in the journal Health Metabolism, has shown that men’s health issues such as stress levels and body weight can have very significant effect on the epigenetic markers in sperm cells. Epigenetics is a study which has revolutionized how scientists view inheritance in nature.
An epigenetic marker or modification is a heritable alteration that is not due to changes in the DNA sequence. On the contrary, these markers alter the accessibility of genetic coding as well as the chromatin structure, which can be attributed to environmental or external factors. These markers, in turn, affect how hereditary characteristics are expressed in subsequent generations.
In the aforementioned research project, researchers from the University of Copenhagen in Denmark looked at sperm from 10 obese men and 13 lean ones to study if there was any genetic markers which could be associated with their weight.
In all the samples collected for the study, the Danish researchers were able to identify very specific markers in the area of the human genome used for controlling appetite. What was revealing though was that the biomarkers were expressed very differently in the two groups. They showed that the weight of a father could very easily affect the appetite of his children and, by extension, their body shape as well.
The researchers were able to follow up on six of the ten obese men who were going through weight-loss surgery. The results were startling to say the least. On average, the researchers were able to identify 5000 changes in DNA markers of the samples collected before and after the surgery. The second samples were collected a year later when the men were much leaner after weight loss surgery.
It is significant to note that the changes identified in the sperm of the erstwhile obese men were not in the structure of the DNA itself or even in the histones. On the contrary, they were invariably located in the associated small RNA molecule. Recent studies have already shown that the RNA does indeed play a significant role as an epigenetic marker, telling the cells which genes to turn on or off.
The Danish study showed that the RNA molecules were responsible for passing on specific hereditary information. In this particular instance, the researchers showed that the RNA molecules clipped on the different parts of the DNA of the sperm cells. Specifically where the RNA molecules clipped to depended on whether they were harvested from lean or obese men.
This study shows that, just like for mothers, there is plenty of diet and health precautions prospective fathers ought to be aware of before (and even after) pregnancy.