In recent years, child rape cases have risen that have shaken society at its peak. However, DNA finger-printing technology has come up as hope to detect the rapists. Pakistani nation took fresh breath after knowing that rapist Imran was involved in Zainab’s sexual assault followed by murder last year. Nothing helped but DNA test that was conducted that helped to establish the status of serial killer (Imran).
By Prof. Dr. Abdullah G Arijo
Ever since DNA test has brought bright light visible, there is debate in personal circles and social media aimed at under mining the importance of DNA finger printing.
All relates to conventional approach and lack of professional knowledge regarding significance of DNA test, DNA finger printing and Gene sequencing.
The use of DNA testing (fingerprinting) in criminal investigations is quite common in western societies. The protocol is novel and legal but some Muslim scholar are divided in their opinion.
Conventionally DNA finger printing has been in different areas including solving (a) Paternity (sorting out carelessly misidentified babies in hospitals; (b) defining the identity of a missing child; (c) deciding actual paternity of a child attributed to someone when another comes forward with clear proof of a paternity claim, or (d) the rare case of a woman impregnated by two men (through concurrent fertilization of two different ova), as in cases of gang rape.
(b) Identity (establishing the identities of prisoners of war, abducted children—who have been gone for an excessively protracted period; verifying the identity of claimants of blood affiliation with a certain ethnic group or person).
( c) Culpability (Establishing criminal guilt from the DNA traces left by criminals (i.e., a body cell, semen, saliva, hair, cigarette butt, blood etc.) as in the cases of rape, fornication, murder, theft, child kidnapping, etc.
DNA test is highly reliable and leaves not question un-answered. One famous case wherein DNA fingerprinting technology was employed to establish guilt is that of the American President Bill Clinton, in his scandalous involvement in an extramarital sexual relationship with Monica Lewinsky. The president’s denial of the affair was refuted when evidence showed the existence of the president’s genetic print in the seminal smear found on Lewinsky’s dress.
What is DNA test and how it may help identify culprit(s) may be understood from certain questions that have been answered here under.
How long does DNA last as evidence?
Researchers believe that, it varies from situation to situation. under ideal conditions, DNA can maintain its molecular shape for about 6.8 million years, after which all the bonds would be broken and sequences may not be readable after about 1.5 million years , researchers believe. The oldest DNA recorded was found in Greenland ice, and estimated to be between 450,000 and 800,000 years.
In case of detecting a rapist, DNA sample from the victim and rapist is required. It is important to note that, sperm DNA may last in the reproductive tract of the victim for seven days or even longer after ejaculation? After sexual assault (act), semen sample from reproductive tract is collected using swab and DNA is extracted using nucleic extraction kits. If it is not possible to get semen sample from reproductive tract, sample may be collected from dry seen drops on any part of body, particularly cloths.
Once semen is collected from victim, complete DNA test may require 24-72 hours. However, researchers are working to increase the speed of forensic DNA testing, and scientists are trying to build a chip that can copy and analyze DNA samples taken from a cotton swab.
To identify the rapist, semen DNA samples from suspected rapist are to be collected, processed and subjected to gel documentation. If DNA from the victim and rapist match, we have result. How long does it take to get forensic DNA results is still an area to think about? The technology has limitations. Most genetic tests take 24-72 hours but the time taken for DNA to go from crime scene to identification can span as long as 14 days.
In case of Zainab, the dead body was found on 7th day after sexual assault and murder. The semen sample may have been collected on swab on which the DNA should last up to 3 months from the time of sample collection.
As mentioned above, the semen samples may be collected from various sources. One needs to establish the route of rape. In case of anal rape, three days and vaginal rape up to seven days may help collect semen sample from dry drops on clothes. Semen can also be detected on clothing despite washing.
Rape in Pakistan came to international attention after the politically sanctioned rape of Mukhtaran Bibi (Khan, Aamer Ahmed, 2005). The group “War Against Rape” documented the severity of rape in Pakistan, and the police indifference to it (Karim, Farhad
1996). According to Women’s Studies professor Shahla Haeri, rape in Pakistan is “often institutionalized and has the tacit and at times the explicit approval of the state” (Haeri, Shahla 2002) According to lawyer Asma Jahangir, who
The investigation protocol to identify rape victim has been conventional and un-reliable. Therefore, there was dire need to establish facilities to be in line with international standards.
DNA test for investigation purposes is new for Pakistan, but, some public and private sector institutions have built capacity for this novel protocol. DNA profiling is used by crime
laboratories for testing biological evidence, most commonly by means of the polymerase chain reaction (PCR), which allows analysis of samples of limited quality and quantity by making millions of copies. An advanced form of PCR testing called short tandem repeats (STR) generates a DNA profile that can be compared to DNA from a suspect or a crime scene. Blood, buccal (inner cheek) swabbing or saliva may also be collected from victims to distinguish their DNA from that of suspects (National Criminal Justice Reference Service, 2004).
DNA–short for deoxyribonucleic acid–was discovered in 1869, however, its vital role in defining genetic inheritance wasn’t established until 1943. In the early1950s, Watson and Crick were only two of many scientists working on figuring out the structure of DNA. It is now believed that DNA is a heredity material and a biological CD of an eukaryotic organism and it is never same in individual of same species, except identical twins as monozygotic twins originate from the same egg/sperm combination, they have the same DNA.
DNA technology has many applications, so, it must be utilized to resolve disputes. Karen M. Sullivan (1994) concluded that, DNA profiling is more sensitive, being able to generate sound data from only a tiny amount of even partially degraded biological material.
It can resolve mixtures of semen or tissue from up to several individuals. It has a far greater power of discrimination between individuals sometimes up to 1 millionfold higher than conventional techniques. It provides considerably more information on the nature of relationships, particularly in cases of incest.
In many parts of world DNA technology is being used in detecting crime. Pakistan must also adopt this trend to address criminal issues.
To begin with, DNA testing labs may be established in each district head quarter. DNA profile of all adult persons may be done and this information may be made part of NADRA data-base. In every hospital, DNA profiling of newborn be done and same must be included into NADRA data base.
This will enable to establish a pool of genetic data of every citizen. It may help in diversified ways. For example, if there has been robing in a house, the culprit must leave some biological signs (such as hand touching on doors, cup boards etc. and even single hair from culprit). This may help extract nucleic acid, which may be confirmed with genetic data base with NADRA authorities and culprit may be caught.
DNA test is not just helpful in detection of rape culprits, but it may help in paternity and maternity, criminal identification and forensics and personal identification and many more.
For crime free Pakistan, it is high time to go for scientific options that world is getting benefits from. All needed is to establish infra/supra structures once.
Authors: Prof. Dr. Abdullah G Arijo Chairman Department of Parasitology Sindh Agriculture University Tandojam