We often hear people saying, "You look after your father," or "You got the looks of your mother."
Genetics plays a big part in that. A child inherits features from parents even before he or she is born.
Because many people think that a mother can directly transfer her illness to her offspring, people are always concerned about her health. However, a recent study by researchers from Walter and Eliza Hall Institute suggests that it is not only the mother's health that should be given emphasis, but also that of the father.
Epigenetic Changes Transmitted to Generations
'Epigenetic Inheritance' is when the genetic code is affected by the way these codes are read by cells. An example of that has been seen in children with fathers who experienced trauma. The physical appearance of children was not affected, but their behavior, like the levels of stress hormones, was observed.
The study by researchers from Walter and Eliza Hall Institute examined the possible effect of infection on fathers from the parasite toxoplasma to the offsprings. The effect is seen on the child's brain health and behavior. The result also reveals that these epigenetic changes may be transferred to generations.
What is Toxoplasma?
Toxoplasma is a common parasite that infects or may be carried by between twenty-five and eighty percent of the population in the whole world.
Animal carriers can transmit this infection. It may severely affect people with weaker immune systems like pregnant women. And because cats can cause toxoplasma infection, pregnant women are often advised to keep away from cat feces.
Toxoplasma infection is associated with manifestations of mental health disorders like bipolar disorder and schizophrenia. Studies have also shown that these infections can have a long-term effect on epigenetic changes in the cells in one's body.
The study of researchers from Walter and Eliza Hall Institute
The group of researchers wanted to know whether epigenetic changes brought by Toxoplasma in mice could be passed to different generations.
To be able to do so, the group of researchers chose to study male mice that had Toxoplasma infection. It was seen that these male mice could only influence their offspring through their sperm cells.
The infection alters the small RNA, which is part of human's DNA. These changes are seen to affect gene expression, and also potentially affects the behavior of a child and brain development. The study also showed that these changes could still influence grandchildren.
The Impact of the study
This study is the very first that showed that epigenetic changes could result in an infection carried by a male and that later on, it may also be transmitted to the next generations.
Although the study examined mice, researchers think they have raised a valid question to the scientific community, as to whether infections to father before conception may also affect their child.
Aside from the Toxoplasma, researchers are also looking into other diseases, including the models fro animals of SARS-CoV-2 virus, the one which is responsible for causing COVID-19.