Obesity and Your DNA

Obesity is a rising problem in The United States and its known that obesity affects the immune system. A new study shows that obesity may be affecting our DNA of our immune cells and causing this problem. The branch of genetics that attempts to explain this phenomenon is called epigenetics. Epigenetics is a relatively new area which reveals that things other than the actual DNA sequence can affect you. The study attempts to show a connection between obesity and a change in the DNA called methylation. DNA methylation is what happens when a carbon atom bonded three hydrogen atoms attaches to a specific area on the DNA strand. A group of scientists: Xiaoling Wang, Haidong Zhu, Harold Snieder, Shaoyong Su, David Munn, Gregory Harshfield, Bernard L Maria, Yanbin Dong, Frank Treiber, Bernard Gutin and Huidong Shi; in which they analyzed the leukocyte, or white blood cell, DNA of both obese and lean individuals and determined to what degree certain areas of the DNA were methylated.
In order to do this, seven obese and seven lean individuals were selected and their leukocyte DNA was analyzed using a HumanMethylation27 BeadChip which allows the scientists to determine the degree of methylation on the areas of DNA in question. They broke up the DNA using special enzymes and analyzed the fragments for these methyl groups. What they saw was that obese individuals had increased methylation levels at one gene and decreased methylation levels at another gene. In other words, obese people did in fact have different methylation levels on their DNA. Their DNA was different from those of lean people of the same age. These differences are not in the code, and they can be changed. That’s one of the things that make epigenetics such a big deal. It shows that the DNA sequence is not all that matters, and since we can change these methylation levels, we can affect what proteins a person’s DNA actually codes for. There are some limitations with this study, like the fact that they only used 7 obese people and 7 lean people. This is a very small sample size, and as such it cannot prove anything. What this study does is show the possibility for obesity to affect DNA. To properly understand and categorize and indeed prove that this actually happens, and to determine the connection between the two will require much larger studies to be done with larger sample sizes. This is important because it shows how obesity affects DNA and the immune system. If this process can be completely understood, then there is the possibility that a medication could be found and produced that could counteract this and return the afflicted’s immune system to its normal state. That time is a long ways away, but still the possibility exists.