A new revolution has begun—the epigenome revolution. Professor Thomas Woodward, a professor and chair of the theology department at Trinity College of Florida, presented new scientific discoveries concerning epigenetics last Thursday in Carson Hall. These new discoveries have challenged and reshaped many pre-existing notions about the human genome and evolution theory.
Until recently, it was believed that 98% of DNA was thought of as junk. But recent discoveries have revealed that certain non-gene areas of the DNA contain information that could regulate the coded gene areas without coding for polypeptides.
“The hyper-complex manager of DNA is the epigenome,” Professor Woodward explained that the genome is just the tip of the iceberg; the epigenome makes up for the rest. “DNA is not your destiny,” he proclaimed, suggesting that other factors could control for gene expression.
Professor Randy Jirtle, professor of Duke and director of the Epigenetics and Imprinting Laboratory, found that a drug called BPA interfered with the regular methylation of the agouti gene upon administration in mice, increasing agouti expression. Agouti normally controls for fur color, but its increased expression leads to obesity, diabetes, and cancer in mice. Looking further into these experiments, scientists discovered that a regular agouti gene has several cytosine bases containing methyl tags, which essentially silence the gene. Furthermore, this epigenetic information could be passed down to the progeny of the affected mice. However, when the offspring were fed a diet full of B-vitamins and methyl, they were found to be healthy.
In our own genes, DNA wraps around histone proteins. These proteins have N-terminal tails, to which specific signals can attach and affect gene regulation. Methyl, acetyl, and phosphate all act as signals that control for the expression of a gene. In addition, SUMO and ubiquitin are also involved in expressing DNA, turning gene expression on and off when appropriate. These tags are added and stripped by certain enzymes, which themselves are regulated by other proteins in a highly complex system that is still not well understood.
Nevertheless, the epigenetics revolution is opening up new channels to improve health and future understanding of human biology. “Epigenetics affects cancer, aging, and all aspects of health,” Woodward explained.
For instance, drug use and smoking can heavily damage the methylation of the epigenetics system, and there is evidence that this epigenetic information can be passed down to future generations. Fortunately, the next generation has the capacity to change the methyl, acetyl, and phosphate tagging on their histones, primarily through healthy behavior such as proper diet, exercise, and sleep.
Epigenetics have been demonstrated in humans as well. Veterans have demonstrated high levels of methyl tagging due to the high amount of stress they undergo while on the battlefield. It was also found that even one trip to the gym could cause the demethylation of certain genes, linking a direct correlation between gene expression and health.
Although epigenetics is still not completely understood, the field looks promising for future studies. “For science, it’s a glorious day,” Woodward remarked.