DNA found at crime scenes can be extremely useful in identifying a perpetrator. But this only works if they have a known suspect and a DNA sample from that suspect, or if the perpetrator is in the national DNA database--CODIS. Without something to compare the crime scene DNA sample against, DNA is not very useful. Same can be said for fingerprints. But perhaps DNA offers something else.
Employing DNA obtained from a crime scene, Familial DNA has been used to narrow the list of potential suspects and this has proven useful in many cases-such as the famous Grim Sleeper serial killer. I have blogged on this before in cases such as The Boston Strangler and the amazing case of Yara Gambirasio.
DNA will of course reveal gender, but there is also research suggesting that race, hair and eye color, and physical features such as stature might also be determined from a DNA sample. These aren't completely worked out yet but they are intriguing aspects of DNA analysis.
But what if a DNA sample could be used to determine the approximate age of the person? This would definitely help as, once again, it would narrow the suspect list. For example, if the crime scene DNA could be shown to have come from someone who was approximately 25 years old it would effectively eliminate a 60-year-old suspect. But is this possible? Maybe.
A new approach, using a process of gene expression called methylation, seems to offer hope. Researchers at the KU Leuven University in Belgium have developed a technique for assessing the degree of methylation in a DNA sample. They believe that this analysis will narrow the age range of the individual down to a four or five year window. If this proves to be true, law enforcement will have another useful forensic science tool.