MethylAGING

Aging is a inevitability that each individual has in common. We all get older and that is something that cannot be changed, unless we get bitten by a vampire and in that case we have immortality. However, this is real life and not fiction. Age of an individual is something that police also looks for when they are explaining a victim or suspect that they are looking for. If there is a body found at a crime scene anthropologists can approximate age by looking at how the teeth are formed and various other osteal markers. However, predicting age without a body present is sometimes hard when you are dealing with a suspect that is alive and the only means of identification are eye-witnesses (sometimes you don't even have that). What if I told you that your DNA could predict how old someone is? You would probably look at me like I'm crazy, however scientists at the Korea Research Institute of Bioscience and Biotechnology have found a way that can age an individual based on the methylation patterns that are present within DNA.

Unfortunately studies have already shown that looking at methylation patterns of DNA could predict age of that individual but it requires a large amount of DNA that forensically is not possible to collect at a crime scene. However, the use of pyrosequencing can be utilized with just 2.5 to 10-ng of starting DNA and is one of the most reliable methods to use to obtain DNA methylation data. This allows the DNA to be quantified and the methylation patterns mapped with just small amounts of DNA that you would normally come into contact with at a crime scene. 

After analyzing the HumanMethylation540 BeadChip the researchers found that the genes ZNF423 and CCDC102B becomes hypomethylated with age while ELOVL2 becomes hypermethylated with age. These three sites were chosen because they were believed to accurately predict age together rather than alone because they all code for proteins are affect aging and they are gender-neutral, which was one of the criteria for the researchers since gender can affect some aspects of aging like balding. 

After looking at the methylation patterns of each of these sites, a linear regression model was created and tested for accuracy . They found that this method could accurately predict age plus or minus 6.8 years, which is way better than not knowing how old the suspect is in the first place (just my opinion). 

There are some limitations to this study. The researchers preformed their experiments using blood that could be found at a crime scene. However, it is known that methylation patterns are tissue specific and there needs to be further research on how different CpG sites are methylated throughout these tissues before where universal methylation markers can be identified. On the other hand, disease plays a role in the deregulation of methylation posing issues that are a problem in determining age by using this method.