2. NUCLEIC ACIDS
• Nucleic acids are the macromolecules present in all living cell.
• FREDRICH MIESCHER was the first person isolated the nucleic acids from
the pus cells. He called it as nuclein.
• As it has an acidic nature, hence ALTMANN called it as nucleic acids.
• The two types of nucleic acids found in living organisms are -
NUCLEIC ACIDS
DEOXYRIBONUCLEIC
ACID [DNA]
RIBONUCLEIC ACID
[RNA]
3. DNA – DEOXYRIBONUCLEIC ACID
• Term given by – ZACHARIS.
• NIRENBERG H HARRIES – Isolation & purification of specific DNA segment from a
living organism.
# CHEMICAL COMPOSITION –
SUGAR MOLECULE
• Identified by LEVENE (1910)
• Pentose sugar - Deoxyribose
PHOSPHORICACID
• As in phosphate group.
NITROGENOUS BASE
• KOSSEL demonstrated +nce pf pyrimidines & purines.
• Awarded with Nobel price in 1910.
4. STRUCTURE OF DNA
• NITROGENOUS BASE:
Nitrogenous base are the
nitrogen containing
compounds.
1. Purines.
2. Pyrimidines.
• PURINES: Purines are the
double ring heterocyclic
structural compounds. The
two types of purines
present in the DNA are
Adenine (A) and Guanine
(G).
NITROGENOUS BASE
PURINES
ADENINE
(A)
GUANINE
(G)
PYRIMIDINES
CYTOSINE
(C)
THYMINE
(T)
5. • NUCLEOSIDES: Compounds formed by the
combination of pentose sugar and
Nitrogenous base is called nucleosides.
They are called as
DEOXYRIBONUCLEOSIDES.
• Adenine + deoxyribose sugar =
Deoxyadenosine.
• Guanine + deoxyribose sugar =
Deoxygaunosine.
• Cytosine + deoxyribose sugar =
• Deoxycytidine.
• Thymine + deoxyribose sugar
=Deoxythymidine.
• NUCLEOTIDES: Compounds formed by the
combination of nucleoside and a phosphate
group is called nucleotides.
• The four types of nucleotides present in the
DNA are -
1. Deoxyadenosine monophosphate.
2. Deoxygaunosine monophosphate.
3. Deoxycytidine monophosphate.
4. Deoxythymidine monophosphate.
N-GLYCOSIDIC LINKAGE
PURINE/
PYRAMIDINE
PENTOSE
SUGAR
NUCLEOSIDE
NUCLEOSIDE PHOSPHATE NUCLEOTIDE
6.
7. • A phosphate group is linked to 5′ -OH of a nucleoside through PHOSPHOESTER
LINKAGE. Two nucleotides are linked through 3′-5′ PHOSPHODIESTER LINKAGE to
form a dinucleotide.
8. • A polymer thus formed has at one end a free phosphate moiety at
5′ -end of ribose sugar, which is referred to as 5’-end of
polynucleotide chain. Similarly, at the other end of the polymer the
ribose has a free 3′ -OH group which is referred to as 3′- end of the
polynucleotide chain.
• Length of the DNA depends upon the number of base pairs +nt.
• Lambda bacteriophage has 48502 base pairs (bp), E. Coli bears
4.6 x 106 bp. A haploid human DNA has 3.3 x 109 bp.
• ERWIN CHARGAFF - QUANTITATIVELY A = T or A/T = 1. This is
also k/as “BASE EQUIVALENCE RULE”.
• QUALITATIVELY C = G or C/G = 1.
• A + G = T + C.
• A + C = G + T.
9. WATSON & CRICK MODEL
• In 1953 that JAMES WATSON and FRANCIS CRICK, based on the X-ray
diffraction data produced by MAURICE WILKINS and ROSALIND
FRANKLIN, proposed a very simple but famous Double Helix model for
the structure of DNA.
• According to Watson and Crick model of DNA, ‘The DNA contains two
polynucleotide strands coiled together in helical manner’. Hence the
name Watson and Crick double helix structure of DNA is given.
# FORMS OF DNA –
• A, B, C, D and Z DNA.
• Among these A, B, C, D are = Right handed helices.
• Watson & Crick model represent the Biotic form of
DNA – B DNA.
# DIFFERENCE IN DNA FORMS –
1. No. of base pairs/turn of helix.
2. The pitch or angle b/w each base pair.
3. Handedness of the double helix.
CHARACTER
A -
DNA
B –
DNA
C –
DNA
D -
DNA
Z -
DNA
BP/TURN 11 10 9.33 8 12
TILT OF BP 20.20 6.30 -7.80 -16.70 70
HELICAL
DIAMETER
23 A0 19A0 19A0 - 18A0
HANDEDNESS Right Right Right Right Left
10. • The two strands of DNA
have the common diameter
of 20 0A.
• Adenine of one strand pairs
with Thymine of another
strand by two hydrogen
bonds and vice versa.
• Guanine of one strand pairs
with Cytosine of another
strand by three hydrogen
bonds and vice versa.
• Each twist of DNA contains
10 base pair.
• The distance between
these two base pairs are
3.4 0A.
DNA
PROMISCUOUS
DNA which makes
movement b/w
mitochondria,
chloroplast &
nucleus
REPETITIVE
Multiple copies of
DNA having
same or almost
same BP
sequence.
Small eukaryotes.
Small highly
repetitive DNA
sequences have
been found.
SATELLITE
11.
12. • One way flow of genetic information from DNA to protein is called central dogma.
• DNA→ RNA→ Protein
# PACKAGING OF DNA IN
PROKARYOTES
• Prokaryotes do not have
definite nucleus.
• The DNA is not scattered
throughout the cell.
• It is held together with some
proteins in a region is called NUCLEOID
• The DNA in nucleoid is organized in large loops held be proteins
CENTRAL DOGMA & PACKAGING
13. • WOODCOCK (1973) has shown that
chromatin consists of a repeating pattern of
bodies k/as NUCLEOSOMES
• HISTONE PROTEINS + DNA =
NUCLEOSOME
• Histones are positively charged due to rich
in basic amino acids residues of Lysine and
arginine.
• Types of Histone proteins –
H2A, H2B, H3 and H4.
1 histone protein has 2 molecules, so 4
histone proteins forms an octamer. An
octamer is aka nu(v8) body.
• The nucleosomes are seen as ‘beads-on-
string’ structure under electron
microscope.
• Nucleosome forms the repeating unit of a
NUCLEOSOMES
15. # TRANSFORMING PRINCIPLE/ BACTERIAL
TRANSFORMATION/ GRIFFITH EFFECT –
• In 1928, FREDERICK GRIFFITH,
conducted experiments to show
transforming principle in bacteria.
• He conducted an experiment on mice and
pneumonia bacteria streptococcus
pneumoniae.
• These bacteria are found in two strains,
as
• 1 virulent (smooth strain) S Strain
• 2 non-virulent (rough strain) R Strain
• The S-strain bacteria produce capsule
and is pathogenic.
• The R-strain lacks capsule and is non
pathogenic.
THE SEARCH FOR GENETIC MATERIAL
16. • When the R-strains are injected into the mouse, it is a non pathogenic and
does not causes pneumonia. The mouse continued to live.
• When the S-strains are injected into the mouse, that causes pneumonia and
mouse dies.
• When heat killed S-strains are injected into the mouse that does not causes
pneumonia. The mouse continued to live.
• When the heat killed S-strains and R-strain are mixed and injected into the
mouse, that causes pneumonia and mouse dies.
# CONCLUSION OF EXPERIMENT:
• R – Strain bacteria had been transformed by the heat killed S-Strain
bacteria.
• The transformation of R-Strain to S-Strain is due to transfer of Genetic
material.
• The biochemical nature of genetic material was not defined from his
experiment.
17. BIOCHEMICAL CHARACTERIZATION OF
TRANSFORMING PRINCIPLE
• OSWALD AVERY, COLIN MACLEOD &
MACLYN MC CARTY. (1933-44) worked to
determine the biochemical nature of the
‘transforming principle’ of Griffith’s
experiment.
• Heat killed S-Strain + protease + Live R-
Strain → transforms R strain to S strain.
• Heat killed S-Strain + RNase + Live R-
Strain → transforms R strain to S strain.
• Heat killed S-Strain + DNase + Live R-
Strain → unable to transforms R strain to
S strain
• # CONCLUSION OF THE EXPERIMENT –
• Protein of heat killed S-Strain is not the
genetic material
• RNA of heat killed S-Strain is not the
genetic material.
• DNA of heat killed S-Strain is the genetic
material.
• – Because DNA digested with DNase
mixed with R-strain unable to transform
R-Strain to S-Strain.
18. • ‘DNA is the genetic material’ is proved by ALFRED
HERSHEY and MARTHA CHASE (1952).
• They worked on the virus that infects bacteria called
bacteriophage.
• During infection the bacteriophage first attaches the
bacteria cell wall. It inserts its genetic material into the
bacterial cell.
• Viruses (T2 bacteriophage) were grown in one of two
isotopic mediums in order to radioactively label a specific
viral component Viruses grown in radioactive sulphur (35S)
had radiolabelled proteins (sulphur is present in proteins
but not DNA)
• Viruses grown in radioactive phosphorus (32P) had
radiolabelled DNA (phosphorus is present in DNA but not
proteins
BACTERIOPHAGE INFECTION
(TRANSDUCTION)
19. 1. REPLICATION - It should be
able to generate its replica.
2. STABILITY - It should be
chemically and structurally
stable.
3. MUTATION - It should provide
slow changes (mutation) that
required for evolution.
4. GENETIC EXPRESSION - It
should be able to express
itself in the form of
‘Mendelian Character’.
REQUIRED
PROPERTIES OF
GENETIC MATERIAL
DIFFERENCE B/W DNA & RNA
20. • DNA replication is a semi – conservative
method or approach. Occurs in S –
phase in cell cycle.
# MECHANISM OF DNA REPLICATION –
• The process of DNA replication takes
place by number of substance, enzymes
and proteins.
• SUBSTANCE: Deoxyribonucleotides.
• ENZYMES: DNA Helicase.
DNA Polymerase III, II, I.
RNA Primase.
DNA ligase.
• PROTEIN: SSB [ Single Strand Binding
protein]
DNA REPLICATION
DNA
POLYMERASE
I
KORNBERG & his
colleagues (1955).
DNA Replication,
proof reading, repair.
Role still
unknownII
III
•T. KORNBERG &
M.L GEFTER.
DNA chain
elongation.
21. 1. RECOGNITION OF THE INITIATION POINT Unwind helix with the help of HELICASE
ENZYME by breaking H bonds. It creates a REPLICATION FORK & ORIGIN OF
REPLICATION (ORI).
2. UNWINDING OF DNA TOPOISOMERASE catalyze and guide the unknotting or
unlinking of DNA by creating transient breaks in the DNA.
3. SINGLE STRANDED BINDING PROTEIN (SSB) – Stabilizes DNA.
4. RNA PRIMING – The DNA dependent RNA polymerase synthesizes RNA Primer. Acts
as a starting point. It works complementary to the template DNA strand. It comprises
of 50 – 100 nucleotides.
5. FORMATION OF DNA ON RNA PRIMER – Done by DNA polymerase in . 5' to
3' direction. Addition of DNA to 3’ end of primer RNA. It is done by DNA Polymerase
III.
LEADING STRAND – 5’ → 3’ CONTINUOUS STRAND.
LAGGING STRAND – 3’ → 5’ DISCONTINUOUS STRAND.
Lagging strand creates OKAZAKI FRAGEMENTS i.e. small fragments. These fragments
are joined by DNA LIGASE.
22. 6. EXCISION OF RNA PRIMERS RNA primer
are removed from 5’ end with the help of
exonuclease DNA polymerase I.
7. JOINING OF OKAZAKI FRAGMENTS – Gaps
between okazaki fragments are filled with
DNA residues by DNA Polymerase I. done
with DNA ligase.
23. EVIDENCE IN SUPPORT OF
SEMICONSERVATIVE MODE OF DNA
REPLICATION
• MESSELSON & STAHL (1958) –
• They grew E. coli on 15NH4Cl culture medium.
• 15N is the heavy isotope of nitrogen
• Both strands of DNA have 15N (15N 15N).
• These bacteria are Shifted to 14NH4Cl culture medium
• DNA extracted subjected to [Cesium Chloride (CsCl)] CsCl
density gradient centrifugations.
• Hybrid/ Intermediate type of DNA (15N 14N)
• After next generation equal amount of light DNA
• (14N 14N) and hybrid DNA (15N 14N) are formed.
24. • S. OCHOA Nobel prize for
artificial synthesis of RNA.
# STRUCTURE OF RNA
• Mostly RNA are single
stranded.
• Sugar – Ribose
• Phosphate – H3PO4.
• Nitrogenous base pair –
PURINE – A & G
PYRAMIDINE – U & C
RIBONUCLEIC ACID (RNA)
TYPES OF RNA
GENETIC RNA
CONRAT established.
RNA acts as a genetic
material.
NON – GENETIC RNA
Do not act as a genetic
material. They are of 3
types –
mRNA, tRNA & rRNA
25. # MESSENGER RNA (mRNA)
• Carries genetic info in cytoplasm for protein
synthesis.
• JACOB and MONOD 1961) named mRNA.
• Template strand for protein synthesis.
• Short life span.
• Total RNA 5%.
# RIBOSOMAL RNA (rRNA)
• In eukaryotes, ribosomes – rRNA occurs as
particles of 4 d/f dimensions – 28S, 18S, 5.8S &
5S.
• Large subunit = 60S
• Small subunit = 40S
• Total RNA 80%.
# TRANSFER RNA (tRNA)
• Comprises of 60 small sized RNA.
• Recognises the codons of mRNA & carries them
to the site of protein synthesis.
• Also k/as SOLUBLE RNA or ADAPTER RNA or
SUPERNATANT RNA.
• Smallest
• 2 sites – 3’ Amino acid group attached
(activated)
Anticodon loop
• Most accepted model of tRNA = CLOVER LEAF
MODEL. ROBERT HOLLEY (1965) + H. G.
KHORANA & NIRENBERG received Nobel prize
(1968).
26. • Sites on tRNA
1. Amino acid attachment site – 3’ end.
2. Site for activating enzyme – dehydovidine or
DH4 loop dictate activation of enzyme.
3. Anticodon or codon recognition site: 3 unpaired bases.
4. Ribosome recognition site – tRNA gets attached to ribosome
# OTHER TYPES OF RNA
1. snRNA Small Nuclear RNA. It helps in splicing, RNA
processing and mRNA processing
HnRNA Heterogenous nuclear RNA. It is a larger molecule.
It is an mRNA precursor
scRNA Small conditional RNA. Small sized RNA. Helps in
taking and binding ribosome + ER.
27. • Formation of RNA from DNA template.
# TRANSCRIPTION UNIT –
1. Promoter
2. Structural gene
3. Terminator
• Parental DNA – Template strand 3’→5’
• Coding strand – 5’→3’ ( It codes for
nothing )
• Promoter is situated towards the 5’ end
of coding strand i.e., at 3’ end of template
strand ahead of structural gene.
• Structural gene is the gene which is to be
transcripted and is +nt on template
strand.
• Terminator is situated towards the 3’ end
of coding strand i.e. at 5’ end of template
strand behind structural gene.
TRANSCRIPTION
28. TRANSCRIPTION
PROCESS
INITIATION
RNA polymerase +
σ sigma, initiation
factor.
The unwinding of
DNA continues till
desired length
through RNA
polymerase II
ELONGATION TERMINATION
RNA polymerase +
rho, terminator
factor
INEUKARYOTES
RNA POLYMERASE I
Transcribes rRNAs 28S,
18S & 5.8S
RNA POLYMERASE II
Transcribes HnRNA
(mRNA precursor)
RNA POLYMERASE III
Transcribes tRNA, 5srRNA,
SnRNA
Normally, mRNA carries the codons of single complete protein –
MONO – CISTRONIC mRNA; several cistrons – POLY CISTRONIC
# SPLICING – DNA comprises of exons and introns
Removal of introns – SPLICING.
HnRNA – capping (5’) Methyl guanosine triphosphate + tailing (3’)
Adenylate residues
29. The mRNA molecule after tailing
and caping moves to cytoplasm as
free nucleoprotein complex k/as
INFORMOSOME.
30. • It is basically that structure of nitrogenous
base in mRNA which possess protein
formation information.
• CRICK discovered it by frame shift mutation.
• CODON Codes for specific amino acid
• NIRENBERG & MATHAEI (1961)
Determined that 3 nitrogenous base
together are k/as triplet codon & they code
for 1 amino acid.
• Genetic code noble prize – KHORANA
# SALIENT FEATURES OF GENETIC CODE
1. Triplet codon
2. Comma less
3. Universal
4. Non – overlapping nucleotides
5. AUG – acts as Initiation codon & codes for
methionine.
6. UAA (Ochre), UGA (Opal) or UAG
(Amber)– Termination codon
WOBBLE POSITION/ HYPOTHESIS First 2
bases of tRNA anticodon specifically undergo
for hydrogen bonding. However, third base can
form unusual base pairing. Because, it can
Wobble, position is called WOBBLE POSITION.
GENETIC CODE
31.
32. • Change of single base pair in the gene – POINT
MUTATION. Example: Sickle cell anemia.
• RAM HAS RED CAP
• RAM HAS BRE DCA P
• RAM HAS BIR EDC AP
• RAM HAS BIG RED CAP
• The same can be repeated, by deleting the letters
R, E and D, one by one and rearranging the
statement to make a triplet word.
• RAM HAS EDC AP
• RAM HAS DCA P
• RAM HAS CAP
• The smallest part of gene that can mutate –
MUTON.
• TAUTOMERISM – Pairing of purine with purine
and pyrimidine with pyrimidine.
• SUBSTITUTIONS/ REPLACEMENTS – These are
gene mutations where one or more nitrogenous
base pairs are changed with others. They are of 3
types –
1. TRANSITION – when in a triplet codon purine
replaces purine & pyrimidine replaces
pyrimidine.
2. TRANSVERSION – purine is replaced by
pyrimidine or vise a versa.
3. FRAME SHIFT/ INSERTION/ DELETION –
addition/ deletion of single base takes place.
None of the codon remains in the same original
position.
• Gene mutations that involve the substitution,
deletion or insertions of more than one base pair
or entire genes – GROSS MUTATIONS.
MUTATIONS AND GENETIC CODE
33. • Process of formation of protein with the help of amino acid chain.
• During transcription mRNA is being formed in the
nucleus which later enters cytoplasm.
• In cytoplasm, mRNA attaches itself with small
ribosomal unit.
• A molecular mechanism by which a gene expresses a phenotype by synthesizing a
protein or an enzyme, which determines the character is k/as GENE EXPRESSION
• It is a process by which information stored in the DNA in the form of genes is used in the
synthesis of functional gene products.
TRANSLATION
Ribosome
Large
subunit (60s)
Small
subunit (40s)
34. • A recognition enzyme attaches itself with large ribosomal unit.
• This complex formed now searches for start codon (AUG) on mRNA & once
found this complex gets attached at that site.
• The P site attaches itself at mRNA
such that tRNA adapter molecule
attaches with the start codon site.
• mRNA is read by the P site and
adapter molecule with requires amino
acid.
• The amino acid joins and forms a chain where as the adapter molecule exit
through the E site.
• The process stops when a stop codon is encountered where a release factor
binds.
• The shift of ribosomes along mRNA is called TRANSLOCATION.
60s
EXIT (E)
PROMOTER/
DONOR/
PEPTIDYL (P)
AMINO-ACYL
/ACCEPTOR (A)
35.
36. • U.S. govt. started Human genome project in 1990 coordinated by the
Department of Energy and the National Institutes of Health.
• GENOME – The whole hereditary information of an organism that is
encoded in the DNA is called genome.
• Human Genome Project (HGP) was called a MEGA PROJECT because -
1. Human genome have approximately 3 x 109 bp. The cost of sequencing
required 3 US $ per bp. Then total estimated cost of the project is 9
billion US dollars.
2. The obtained sequences were to be stored in typed form in books. If
each page of the book contained 1000 letters. each book contained 1000
pages. Then 3300 such books need to store information from a single
human cell.
HUMAN GENOME PROJECT
37. AIMS OR GOALS OF HUMAN
GENOME PROJECT
1. Identify all the approximately 20,000-
25,000 genes in human DNA;
2. Determine the sequences of the 3
billion chemical base pairs that make
up human DNA;
3. Store this information in databases;
4. Improve tools for data analysis;
5. Transfer related technologies to other
sectors, such as industries;
6. Address the ethical, legal, and social
issues (ELSI) that may arise from the
project.
# METHODOLOGIES–
1. Identifying all the genes that
expressed as RNA (Expressed
Sequence Tags - ESTs).
2. Blind approach of simply sequencing
the whole set of genome. That
contained all the coding and
noncoding sequence. later assigning
different regions in the sequence with
functions (Sequence Annotation
38. # SALIENT FEATURES OF HUMAN GENOME PROJECT –
1. The human genome contains 3164.7 million nucleotide bases.
2. The average gene consists of 3000 bases, but sizes vary greatly, with the largest
known human gene being dystrophin at 2.4 million bases.
3. The total number of genes is estimated at 30,000– much lower than previous
estimates of 80,000 to 1,40,000 genes. Almost all (99.9 per cent) nucleotide bases
are exactly the same in all people.
4. The functions are unknown for over 50 per cent of discovered genes.
5. Less than 2 per cent of the genome codes for proteins.
6. Repeated sequences make up very large portion of the human genome.
7. Repetitive sequences are stretches of DNA sequences that are repeated many
times, sometimes hundred to thousand times. They are thought to have no direct
coding functions, but they shed light on chromosome structure, dynamics and
evolution.
8. Chromosome 1 has most genes (2968), and the Y has the fewest (231).
9. Scientists have identified about 1.4 million locations where single- base DNA
differences (SNPs – single nucleotide polymorphism, pronounced as ‘snips’) occur
39. • Gene regulation is the ability of a cell to control or regulate what proteins it makes
from its DNA.
• French scientist JACOB & MONOD (1961) - OPERON – Segment of DNA i.e. genetic
material which function as regulated unit that can be switched on and off.
• Experimentally they demonstrated the regulation of gene in E.coli.
• The sequential arrangement of regulatory gene, promoter gene, operator gene and
structural genes in prokaryotes is called operon concept.
• REGULATORY SEQUENCE – few 100s to 1000s base pair long. Behind main protein
coding genes. It is site of attachment fro enzyme RNA polymerase.
• REGULATORY GENES lie few 1000s base pairs away/ behind the protein coding
genes. They synthesizes a protein c/as REGULATORY PROTEIN This protein goes
and control binding of RNA polymerase to regulatory sequence.
• Regulatory sequence – regions – PROMOTER(P); OPERATOR(O); REPRESSOR(I).
LAC OPERON/ INDUCIBLE LAC OPERON
40. • Structural gene – genes
producing mRNA.
• Z = produces β
galactosidase – breaks
lactose into galactose
and glucose.
• Y = produces
galactoside permease –
increases permeability
for β galactosidase.
• A = produces enzyme
transacetylase –
function not known yet.
41. • Given by ALEC JEFFERY in 1985
• DNA fingerprinting involves identifying
differences in some specific regions in DNA
sequence called as repetitive DNA.
• These repetitive DNA are separated from
bulk genomic DNA at different peaks during
density gradient centrifugation. The bulk
DNA forms a major peak and the other small
peaks are referred to as satellite DNA.
• These sequences show high degree of
polymorphism and form basis of DNA
fingerprinting.
• The principle of DNA finger printing is based
on matching of VNTRs of DNA collected at
crime spot with suspect person DNA.
• VNTRs VARIABLE NUMBER OF TANDEM
REPEATS It is also called as mini satellites
that shows very high degree of
polymorphism.
• VNTRs are very specific to individual and
differs from person to person.
• SOUTHERN BLOTTING It is the technique of
transferring DNA from agar gel to nylon
sheath.
• PROBE Single stranded polynucleotide
fragment complementary to specific
sequence of nucleotides of
• DNA is called probe. It is mainly used in
identify VNTRs and desired gene
DNA FINGERPRINTING
42. # METHOD OF DNA FINGERPRINTING
–
1. Isolation of DNA.
2. Digestion of DNA by restriction
endonucleases.
3. Separation of DNA fragments by
electrophoresis.
4. Transferring (SOUTHERN
BLOTTING) of separated DNA
fragments to nylon sheath.
5. Hhybridization using labelled VNTR
probe,.
6. Detection of hybridized DNA
fragments by autoradiography.
43. APPLICATION OF DNA FINGER
PRINTING TECHNOLOGY
1. It is used to identify criminals
and rapist.
2. To solve parental dispute.
3. To solve immigrant problems.
4. To identify dead bodies of
soldiers died in wars.
5. To identify dead bodies of
person died at accidents and
bomb blast.
6. To identify racial groups.
7. To detect inheritable disorders.
8. To detect donor cell in case of
transplantation.