A one-of-its kind workshop at the Institute of Forensic Medicine at the Rajiv Gandhi Government General Hospital in Chennai threw up interesting facets of a subject that is of utmost importance to the police and the investigators.
Laymen are perhaps aware of investigation, the fieldwork that police do. They bring the victim to the forensic medicine doctor who gathers evidence and provides the investigating officer clues to finding the perpetrator of the crime. A forensic medicine doctor conducts the post-mortem and examines the wounds on the body of the victim and makes meticulous notes. He/she also follows instructions from the investigating police officer who wants samples of tissue or bone and tooth for DNA analysis at a later date.
“The investigating officer always wants us to provide the longest bone or the toughest tooth in the body for DNA analysis. Extracting it is time consuming. A simpler method would not only be safe but also make the job easy for us,” B. Santhakumar, head of the institute, says. It was modern technology that helped identify the dismembered parts of former Prime Minister Rajiv Gandhi who was killed in Sriperumbudur by human bomb Dhanu in 1991, he adds.
Tamil Nadu thus became the first in the country to adopt modern technology in collecting samples, says Kamalakshi Krishnamurthy, deputy director, DNA Division of the State Forensic Science Department. “There are easier methods which are safer and can be stored for at least 20 years,” she says.
According to these experts, FTA card (Flinders Technology of Australia), a small card half the size of a visiting card, is used to collect blood and body fluid samples. Just two drops on the card is enough evidence for DNA analysis purposes, the experts say. Such cards have helped solve several murders, identify the dead in disaster zones and perpetrators of sexual assault, says Dr. Kamalakshi.
In fact, it has also helped prevent embarrassment to the government sometimes. Sometime ago, a family refused to accept the remains of their 28-year-old kin after one eye was found missing. The general belief was that rodents had feasted on it. The man was a victim of murder in Cuddalore. Some days later the eye was found and using the FTA card, the department proved that it was the murder victim's eye. FTA cards are most useful in determining paternity and maternity suits. A drop of blood from the parents or the children is enough to establish the genetic connection. Forensic experts have used it to ascertain a kidnapped child's biological parents.
Several years ago, two parents claimed ownership of a boy child born in a government maternity hospital in Chennai. Both sets of parents refused to claim the girl child while seeking to own the boy baby. Finally DNA tests were done to settle the dispute.
While the workshop focused on forensic doctors, the forensic science experts plan to hold hands-on workshops for investigating police officers and doctors in the casualty departments of hospitals too.
Keywords: forensic medicine