Touch DNA: How NIA used it to crack cases?

Touch DNA is a forensic method to analyse the DNA left at the crime scene. If one looks at the manner in which the National Investigating Agency has gone about solving several cases, it becomes clear that they are exploring every possible method and are constantly upgrading their investigating techniques to beat the terrorists at their own game.

Most of the recent cases that were handled by the NIA relied on the Touch DNA methodology and it has proven to be a major success for the agency. Be it the Patna and Bodhgaya blasts case or even the recent Liaqat Shah incident, the success rate was 100 per cent thanks to the out of the box thinking and the right use of forensics and technology.

What is touch DNA?

Police officials especially in Bengaluru very often complain that they have no evidence to go ahead in a case. Take for example the Church Street blasts case which is turning out to be one of the world's greatest mysteries.

Touch DNA if relied upon does have a great success rate in solving a crime. It is a forensic method of analyzing the DNA left at the scene of the crime. The reason it is called as Touch DNA is because it requires very small samples left behind at the crime scene.

Touch DNA could sample skin cells which are left on the object. It requires just seven cells from the outermost layer of the human skin. Once the samples are gathered and sent for analysis it can get the perfect results to track down the criminal.

Caution to be exercised

The NIA appears to have mastered the art of Touch DNA. While it is a great way of solving a crime, it also has its drawbacks. The person collecting the samples needs to be extremely cautious. When Touch DNA samples are being collected the officer uses a brush. He needs to be careful as the samples from his skin could transfer on to the object and this could lead to incorrect results.

Due to these intricate details that are required to be observed, investigating officers with specialization need to handle it. However at the moment it could act as a major lead in an investigation. The officer needs to be extremely confident that the samples have been collected correctly and his own samples have not been transferred to the object.

Cracking the Bodhgaya case with Touch DNA

In the Bodhgaya blasts case, the bomber was masked and disguised as a monk. Even though there was CCTV footage, it was difficult for the NIA to come to any conclusion. After planting the bomb, the bomber left the monk's robe behind.

The Touch DNA sampling was put into effect and the skill cell samples were collected from the robe. During this exercise it was found that an operative by the name Numan was also part of the bombing. He had left for his home in Ranchi and the agency managed to find his whereabouts.

However on reaching Ranchi, it was found that he had left the place, but he had kept his bag behind. The Touch DNA method was used yet again and the samples collected from the bag and matched.