DNA Fingerprinting Technology - Its Success and Future

Some proportion of DNA sequence of every individual is unique. There are probes that can find such unique DNA sequences and generate individual-specific DNA profile. This can be visualized as bands by molecular biology techniques. In 1988, CSIR-CCMB scientists developed indigenous probes for DNA fingerprinting and took this technique to the users. India, thus, became the third country in the world to develop its own DNA fingerprinting probe.

The technique was a fall-out of the basic research on molecular basis of sex determination in snakes. The probe was obtained from the minor satellite DNA of the Indian banded krait snake. And they found that the probes from snakes could work on human DNA too. The scientists found individual-specific DNA banding pattern using these probes. Thus, it could be used for establishing identity of people as fingerprints and handwriting of people have been used more traditionally.

In 1991, DNA fingerprinting evidence was presented in the Kerala High Court in a paternity dispute case. And for the first time in the annals of the history of Indian Judiciary it was accepted as an infallible evidence in the court of law.

Since then, CSIR-CCMB has used this indigenous technique in hundreds of cases including paternity disputes, identification of missing children, identification of mutilated bodies, exchange of babies in maternity wards and cases of rape and murder, among others. These include sensational cases of assassination of the late Prime Minister Shri Rajiv Gandhi, assassination of Punjab Chief Minister, the famous Tandoor murder case of Naina Sahni and busting the Swami Premananda scandal.

Figure 2: Media coverage on acceptance of DNA fingerprinting data in legal action

Data from DNA fingerprinting technology is considered unbiased, unfabricated and 99.9% accurate. Legal courts accept that no two individuals have the same DNA standard. Based on the success of the technology, a separate autonomous institute, ‘Centre for DNA Fingerprinting and Diagnostics (CDFD)’ has been set up by the Department of Biotechnology, Ministry of Science and Technology, Government of India. The Centre regularly receives samples from the investigating agencies for establishing DNA identity of individuals. CDFD and CSIR-CCMB maintain strong bonds with court judges to explain them how the technology works. In addition, there are about 30 other State and Central Forensic Laboratories in the country that can now do such tests.

DNA Fingerprinting has seen success in:

  • Establishing paternity and maternity
  • Identification of a missing child and mutilated body
  • Identification of criminals in cases of rape, murder and assassination
  • Immigration purposes
  • Pedigree analysis of farm animals
  • Assessment of inbreeding
  • Plant variety identification
  • Sexing of biological samples
  • Wildlife forensics
  • Wildlife conservation
  • Biodiversity conservation

It is also important to note that the technology establishes individual’s identity by probing only a very small variable region of their DNA. This region does not lead to any information such as their medical history or ethnic background.

Future of DNA fingerprinting in India:

India has used DNA fingerprinting for establishing guilt in suspects and convicts of court cases. However, the technology can be equally useful in establishing innocence of suspects and convicts. India is yet to have made use of this technology for saving people from wrongful convictions. The Indian legal system also has very limited sections that mention DNA. Wherever it does, it only talks of the procedures and situations under which DNA samples are collected from the accused and the victim.

The Indian legal system accepts DNA fingerprinting as a corroborative and not a conclusive evidence yet. The biggest hindrances are the lack of regulations of sample collection and data storage, and lack of clarity on the kind of information that the DNA fingerprinting data holds. The technology also brings fear of violation of right of privacy, dignity, assumption of innocence, health and others. It triggers insecurities in minorities in our society. There is discrepancy on how long the data will be available, and how it can be used by people in other cases. There have been cases of data fraudulence in the country. All of these put together, only 2-3% legal cases in India avail DNA fingerprinting technology.

On the other hand, India has an estimated 40,000 unidentified bodies. About a lac of children go missing each year. These could all benefit from usage of DNA fingerprinting technology if the regulations are more structured. The current DNA bill in India seeks to address quality, accuracy and security of data and related matters. It aims to establish DNA Regulatory Board that will lay guidelines, standards and procedures for establishment and functioning of testing labs and DNA data banks. The country hopes that the bill addresses many of the current gaps so that DNA fingerprinting technology goes beyond select cases, and becomes a more regular norm in legal procedures.

Somdatta Karak & K Thangaraj