Information about DNA & RNA , How its Works and related provisions in law and famous case laws insight in India.

1. DNA AND RNA
Sayali Dilip Morankar
(Medical Jurisprudence And Forensic Science)

2. 1.CONCEPT
WHAT IS DNA ANALYSIS ?
DNA analysis is an examination method that emerged in the mid 1980’s by Alec
Jeffrey's, an English geneticist.
DNA is deoxyribonucleic acid, which is a double stranded lung molecule
and appears like a twisted rope ladder or double helix. Alternating phosphate and
deoxyribose sugar units comprise the sides of the ladder, while the connectors of
the ladder are composed of bases known as adenine (a)thymine (T)guanine
(G)cytosine.
DNA is essentially made up of amino acids and it is matched with the so-
called bases which provide the key to determining the genetic blueprint.

3. HOW DOES IT WORK?
• Any organism can be identified by examination of DNA sequences
unique to the specific species.
• To identify individuals, forensic scientist scan 13 DNA regions (loci)
and create a DNA profile for that individual (DNA fingerprint).
• There’s a very slim chance that another individual has the same DNA
profile for a specific set of 13 loci’s.

4. EFFECTIVENESS OF DNA
• DNA Identification is quite effective when used correctly.
• Portion of DNA sequence that vary the most among humans must be
used.
• Portions must also be large enough to factor in the fact that human
mating is not absolutely random.

5. EXAMPLES OF DNA IN FORENSICS
• Identify potential suspects whose DNA may match evidence left at
crime scene.
• Exonerate persons wrongly accused of crimes.
• Identify crime and catastrophe victims.
• Establish paternity and other family relationships.

6. DNA TECHNOLOGY
• CODTS, which stands for combined DNA index system, is a program
which consists of many databases that have DNA profiles useful for the
criminal justice system.
• The NDTS, or National DNA Index System is the part of CODTS that
contains the DNA profile at a national, state and local level and is
accessible to law enforcement all over the country.

7. DNA TESTING PROCEDURES
• Although , there are numerous types of procedures adopted for forensic matching
and identification of an individual, there are two main types of such testing systems
. They are called Restriction Fragment Length Polymorphism,(RFLP) and Polymerase
Chain Reaction (PCR)testing.
• Generally RFLP testing process requires larger amounts of DNA and for proper
results the DNA must be uncontaminated . Small amounts of DNA sample is not
suited for RFLP testing whereas PCR testing require smaller amount of DNA sample.
However this test is highly sensitive test and the slightest contaminants at the scene
of crime can alter or influence the results.

8. WHAT IS DNA EVIDENCE?
• DNA evidence is playing a larger role than ever before in criminal cases
throughout the country, both to convict the guilty and to exonerate those wrongly
accused or convicted. This increased role places greater importance on the ability
of victim service providers to understand the potential significance of DNA
evidence in their clients cases.
• Degradation is also a common concern with DNA samples.
• Collection and storage must be carefully monitored to prevent bacteria growth.
• Evidence collected for the purpose of blood type testing may be stored according to
that type of taste and may limit chances of testing DNA in the sample.
• In same cases, DNA has been successfully extracted and analyzed from a moldy
sample with the help of PCR technology.

9. VALUE OF DNA EVIDENCE
• DNA is a powerful investigative tool because, with the exception of identical twins, no two
people have the same DNA. Therefore DNA evidence collected from a crime scene can be
linked to a suspect or can eliminate a suspect from suspicion.
• The effective use of DNA as evidence may also require the collection and analysis of
elimination samples to determine the exact source of the DNA .Elimination samples may be
taken from anyone who had lawful access to the crime scene and may have left biological
material.
• When investigating a rape case, for example, it may be necessary to obtain an elimination
sample from everyone who had consensual intercourse with the victim within 72 hours of
the alleged assault to account for the entire DNA found om the victim or at the crime
scene. Comparing DNA profiles from the evidence with elimination samples may help
clarify the results.

10. 2.LEGAL PROVISIONS:-
• The code of criminal procedure and the Indian Evidence Act were enacted at a time when
modern scientific advancement and DNA tests were not even in the contemplation of
parliament or legislature. Worldwide, it has been proven that the results of DNA tests, if
conducted in confirmative with modern and latest protocol and the subjects are
scientifically accurate.
• There is an urgent need to incorporate some provision in the Indian Evidence Act 1872,
and the Code of Criminal Procedure 1973, to manage science and technology issues.
• Due to lack of provision, investigating officers face troubles in collecting evidence that
involves modern mechanism to prove the accused guilty.
• Section 53 of the Code of Criminal Procedure 1973 authorizes a police officers to get the
assistance of the medical practitioner in good faith for the purpose of the investigation. But
it does not enable a complainant to collect blood, semen etc. For bringing criminal charges
against the accused.

11. • The Criminal Procedure Code Amendment Act 2005 has brought two new sections
which authorized the investigating officers to collect the DNA samples from the
body of accused and the victim with the help of medical practitioner.
• Right to privacy has been included under right to life and personal liberty or
Article 21 of the Indian Constitution.
• Article 20 (3) provides right against self incrimination which protects on
protection accused in criminal cases from providing evidence against himself or
evidence which can make him guilty.
• The govt. of India and Law Commission have also woken up and Indian
Parliamentary Affairs Board has set up an Advisory committee to give a
comprehensive report on all aspects of DNA testing. The law Commission in its 185
report has also recommended the inclusion on DNA testing in the Indian Evidence
Act by amending its section 112.

12. Right to privacy
Right to privacy is derived from Article
21 of the Constitution and from
Directive Principles of State Policy and
it was held in Peoples Union for Civil
Liberties v/s Union of India, that right
to privacy enshrined in Article 21
cannot be curtailed except according
to procedure established by law.
In the famous case in relation to
DNA investigation Sharda v/s
Dharmapala , the Hon’ble
supreme court discussed the right
to privacy in a systematic
chronological order.
The Identification of prisoners
act 1920
This act enables the investigation
officers to collect fingerprint
impression , foot-print
impressions from the suspect.
Section 5 of the act empowers for
magistrate to order a person to be
measured or photographed.
Here measurement means and
includes finger impressions and
foot-print impressions.
DNA evidence and the privilege
against self incrimination
The discovery of genetic
fingerprinting with its high
specificity and extraordinary
probative properties highlights
the question of the scope of the
privilege against self –
incrimination.

13. COMPARATIVE ANALYSIS OF DIFFERENT
COUNTRIES
• Present world is the world of science and technology. The glob has progressed at
higher speed . Advanced scientific technology has given the world various effective
tools for criminal investigation. With the advancement of science , new challenges
would emerge before administration of every country.
• To meet new challenges and for the welfare of citizen every country try to adopt
new scientific development in the form of various legislation so that they can be
used effectively in the administration of justice.
• Almost every country of the world have given the provision of scientific
developments in their Constitution of the welfare of their citizens and country.

14. IN UNITED STATES
• In U.S.A. DNA testing is done to supplement the traditional blood typing test such as HLA
(Human Leukocyte Antigen) test to resolve a routine paternity test. In DNA more than 30
variables genes are available for matching.
• For DNA testing blood is collected from the child and the bar ( bond) pattern of the child is
first matched with that of mother and thereafter remaining bars are matched with that of
father.
• In blood testing certain safeguards must be observed e.g. the blood must be unaffected of
climate, age, disease or of any other environmental genetic condition and mode of
inheritance of blood must be certain.
• In the last 10 years DNA technology has significantly advanced to more discriminating
methods. The introduction of DNA profiling has revolutionized forensic science and the
criminal justice system by providing courts a means of identifying perpetrators with a high
degree of confidence.

15. IN SWEDEN
• In 1990 Dutch Supreme Court admitted the use of DNA as exculpatory evidence. A new DNA
legislation was incorporated in the Dutch Code of Criminal Procedure, which focuses non-
consenting defendants to give biological reference samples, and the results of the DNA test can be
used as proof of guilt.
IN FRANCE
The consent of interested parties is mandatory with the restriction that in case of a suspect, his refusal
can be interpreted as a prima – facie evidence.
It is clear from the positions of different countries that DNA evidence is admissible in every
country in one from or the other. No other scientific technique has gained much widespread
acceptance so quickly and no other technique has been potentially as valuable to the criminal justice
system as the DNA.
But this scientific technique has not been adopted by Indian legislation like other countries.

16. CASE LAWS
• In Govind Sing V/s State of Madhya Pradesh - Supreme Court held that a
fundamental right must be subject to restriction on the basis of compelling public
interest. It is clear from various decision which have been delivered by the
Supreme Court from time to time that the right to light and personal liberty which
has been guaranteed under our Indian constitutions not an absolute one and it can
be subject to some restriction.
• And it is this basis that the constitutionality of the laws affecting right to life
and personal liberty are upheld by the Supreme Court which includes medical
examination and it is on the basis that various courts in the country have allowed
DNA technology to be used in the investigation and in producing evidence.
•

17. • In Shri.Rohit Shekhar V/s Narayan Dutt Tiwari and Anr. - In which the court
has gone a step further in peculiar facts of this case, the petitioner , who was born
during a subsisting marriage of her mother, asked for DNA test on the respondent,
claiming the later to be this biological father. The court has ordered DNA test on
the respondent a third party to marriage, primarily recognizing from various
international convenants, the right of a child to know of his biological antecedents.
However the Court has been cautious to judgments of the Hon’ble Supreme Court
in Sharda (supra) and Bhabani Prasad Jena and justified on reasons a prima facie
case for ordering DNA test.
• In Madan Gopal Kakkad V/s Naval Dubey and Another - It was held that
opinion of expert is admissible.

18. • In Machindra V/s Sajjan Galpha Rankhama - has observed that an expert
opinion of should be demonstrative and supported by convincing reasons.
• In Selvi V/s State of Karnataka - while testing the validity of DNA test on the
anvil of Article 20(3) of the constitution of India, made following observations -
The matching of DNA samples is emerging as a vital tool for linking suspects to
specific criminal acts. It may also be recalled that as per the majority decision of
Kathi Kalu Oghad (AIR 1961 SC 1808), the use of material samples such as
fingerprints for the purpose of comparison and identification does not amount to a
testimonial act for the purpose of Article 20(3) . Hence , the taking and retention of
DNA samples which are in the nature of physical evidence does not face
constitutional hurdles in the Indian context.

19. WHAT IS RNA ?
• RNA means RIBOSE NUCLEIC ACID . A nucleic acid that carries the genetic
message from DNA to ribosomes and is involved in the process of protein synthesis
is referred to as RNA (RIBOSE NUCLEIC ACID.)
• Ribonucleic acid is one of the two types of nucleic acids found in all cells.
• RNA is similar to DNA but containing ribose in place of deoxyribose and uracil in
place of thymine.
• Some viruses use RNA instead of DNA as their genetic material.

20. HISTORY OF RNA
• Nucleic acids were discovered in 1868 by Friedrich Miescher, who called the
material ‘nucleon’ since it was found in the nucleus. The role of RNA in protein
synthesis was suspected already in 1939. Sivero Ochoa won the 1959 Nobel Prize
in Medicine after he discovered an enzyme that can synthesize RNA in the
laboratory.
• Each nucleotide consists of three components : a nitrogenous heterocyclic base,
which is either a purine or a pyrimidine ; a pentose sugar; and a phosphate group.
• Nucleic acids are universal in living things, as they are found in all cells and
viruses.
• Nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).

21. STRUCTURE OF RNA
• RNA like DNA is a polynucleotide. RNA is either single stranded or double stranded
but not helical like DNA.
• RNA nucleotides have ribose sugar, which participate in the formation of sugar
phosphate backbone of RNA.
• The nitrogen base in RNA are: Adenine(A), Guanine(G), Cytosine (C) , and Uracil
(U). Thymine is absent and is replaced by Uracil. Usually RNA is a single stranded
structure.
• RNA does not form an analogous helical structure.
• RNA form a heteromeric double helix.

22. FEATURES OF RNA
• Location : In eukaryotes, RNA is found both in nucleus and cytoplasm. In the
nucleus it is a components of chromosomes, whereas in cytoplasm it its found in
ribosomes. In prokaryotes, it is found in the cytoplasm.
• Size : RNA molecule is much smaller in size than DNA. It consists up to
12,000 nucleotides whereas DNA consists up to 4.2 million nucleotides.
• Functions : In most of the organisms, the usual function of RNA is transfer of
genetic message from nucleus to the cytoplasm and synthesis of protein in
ribosomes. In some viruses, RNA acts as the genetic material and regulates the gene
action.

23. TYPES OF RNA
• Transfer RNA (tRNA) :
• It is also known as soluble RNA (sRNA).
• It constitutes about 10-15% of total RNA of the cell.
• It is a class of RNA which is of small size of 3S type and generally have 70-90
nucleotides.
• Its main function is to carry various type of amino acids and attach them to mRNA
template for synthesis of protein.
• It has molecular weight of about 25,000 to 30,000 with sedimentation coefficient
of 3.8S.

24. • Ribosomal RNA (rRNA) :
• It is found in ribosome in the cytoplasm.
• It is the catalytic component of the ribosomes.
• The size of ribosome is expressed in terms of ‘S’ units, based on the rate of
sedimentation in an ultracentrifuge.
• It constitutes about 80 % of the total cellular RNA .
• The function of rRNA is binding of mRNA and tRNA to ribosomes in the cytoplasm.

25. • Messenger RNA (mRNA) :
• It constitutes about 5- 10 % of the total cellular RNA.
• It is most heterogenous in size and base sequence.
• It is a single stranded copy of one of the DNA strands of a gene.
• It carries the information from nuclear DNA to cytoplasm for protein synthesis. It is
also known as template RNA.
• The molecular weight of an average molecule of mRNA is 5,00,00 and its
sedimentation coefficient is 8S.

26. DIFFERENCE BETWEEN DNA AND RNA
• First : RNA and DNA are both nucleic acids, but differ in three main ways. Unlike
DNA, Which is in general, double- stranded, RNA is a single – stranded molecule in
many of its biological roles and has a much shorter chain of nucleotides.
• Second : while DNA contains deoxyribose, RNA contains ribose (in deoxyribose
there is no hydroxyl group attached to the pentose ring in the 2’ position ). These
hydroxyl groups make RNA less stable than DNA because it is more prone to
hydrolysis.
• Third : the complementary base to adenine is not thymine, as it is in DNA, but
rather uracil , which is an unmethylated form of thymine.
• Fourth : DNA is generally stable in alkaline conditions while RNA is unstable
during alkaline condition.

27. CONCLUSION
• Thus DNA test as evidence of identity has come to be recognized in our judicial system.
James D Watson one of the discoverers of DNA who was awarded the 1962 Nobel Prize for
medicine for the same, has made the following observations about handling of DNA
evidence, keeping tract of molecular evidence, as opposed to knives and guns, can be an
especially demanding chore; scrapings from a side walk may be visually indistinguishable
from scrapings from a gatepost, and subsequently extracted DNA samples will doubtless
look even more alike when placed in a small plastic test tubes.
• DNA test is a strong boon in criminal administration of justice, but in civil cases the socio
economic condition and the pecullarity in our country declare this test against of human
dignity especially of child and woman. But the inherent power of courts in civil matters
Sec.151 C.P.C.1908 should prevail for the sake of justice, truth and dignity of innocent
person and transparency of judicial administration.

28. • It can be said that our country’s criminal justice system needs a drastic change
either by making new law on DNA testing or to ament other laws. As compare to
other countries our position is too bad because till today we are relying on Indian
Evidence Act.1872 for the criminal justice system. This act was passed at the time
when there was no any scientific technique was existed. But now we are living in
the age of science and technology we have to adopt all advancements to meet the
challenges of present world.

29. THANK YOU