Introduction Genome mapping History Genetic mapping Genetic markers Linkage mapping Recombination frequency Physical mapping Uses of genomic mapping Limitation References

1. GENOMIC MAPPING
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By
KAUSHAL KUMAR SAHU
Assistant Professor (Ad Hoc)
Department of Biotechnology
Govt. Digvijay Autonomous P. G. College
Raj-Nandgaon ( C. G. )

2. CONTENTS
• Introduction
• Genome mapping
• History
• Genetic mapping
• Genetic markers
• Linkage mapping
• Recombination frequency
• Physical mapping
• Uses of genomic mapping
• Limitation
• References
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3. INTRODUCTION
• Gene mapping:describes the methods used to
identify the locus of a gene and the distance
between the genes.
• The essence of all genomic mapping is to place a
collection of markers onto their respective
positions on the genome. Molecular markers
comes in all form. Genes can be viewed as one
special type of genetic marker in the construction
of genomic maps,and mapper the same way as
any other marker.
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4. GENOME MAPPING
• Genetic mapping is based on the use of genetic
techniques to construct maps showing the
position of the genes and other sequence feature
of the genome
-genetic technique including cross-breeding experiments.
-case of human and examination of family history.
• Physical mapping uses molecular biology
techniques to examine DNA molecules directly in
order to construct maps showing the positions of
sequence feature including genes.
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5. HISTORY
• The science of the genetics has progressed in
a very rapid pace.
• But this all began at the 1866 when Mendel
described the inheritance pattern of
conceptual heridatery units.
• In 1907 it was suggested that chromosome
where the carriers of the gene.
• So in 1910 the linkage concept and in 1913 1st
ever linkage map was developed.
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6. GENETIC MAPPING
• Basically genomic mapping means locating a
particular region so that the way of route can
be estimated
GENES GENOTYPE PHENOTYPE
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7. Genetic
map
Linkage
map
Physical
map
By this we can tell
if the genes that
are of target 2 in
no are closely
linked or far away
By utilizing this we
can tell whether a
gene is present on
which of the
chromosome.which
is exact at that place
But both of the above test give different type of data so combining this two type
of data gives the exact location and position of that desired gene
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8. GENETIC MARKERS
• Let us consider that the gene is a marker.
Genes
visible biochemical Molecular
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9. Types of markers that can be used
1. Naked eye polymorphism:that can be
visualized by eye
2. Protein based marker.
3. DNA markers
• RFLP-restriction fragment lenth
polymorphism in this technique the
restriction enzyme is used and the DNA of
different lenth is obtain gives a proper idea
about the position of genes.
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10. • RAPIDs-Random amplified polymorphic DNA.
• AFLP-amplified fragment lenth polymorphism.
• Microsatellites:
• Minisatellites:they do not constituteas a good
marker because these minisatellite region ar
econcentrated at the pro-terminal region of
the human genome
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12. LINKAGE MAPPING
• The two genes are compared just to their
linkage.
• Only in the case of linear DNA
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13. RECOMBINATION FREQUENCY
• the data of the progeny is put into the formula
given below
recombination frequency = r ×100%
p+r
• The observed value is said to be Mu or
Centimorgan (cM)
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14. PHYSICAL MAPPING
• Sequential arrangement of genes are required
this is called as framework map.
• Method utilized:
1.somatic cell hybridization
2.radiation treated cell mapping
3.FISH
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15. SOMATIC CELL HYBRIDIZATION
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18. FISH
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19. SEQUENCING OF DNA
• In mapping process the shotgun DNA
sequencing is used due to the large size of
genomic DNA.
• In this the genomic DNA is broken Down into
several smallere fragments
• Now each fragment is seperatly analysed and
input into a software program which
assembles the overlapping ends and whole
sequence can be analysed.
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20. USES OF GENOMIC MAPPING
• Identify the genes responsible for diseases
- heritable disease
- cancers
• To identify the genes reponsible for the traits.
- plants and animals
- disease resistancy
- meat or milk production
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21. HUMAN GENOME PROJECT
• The human genome project is an international
scientific research project with the goal of
determining the sequence of chemical base
pair which make up the human DNA and for
identifying and mapping all the genes present
in the human genome.
• The human genome project is focused on the
mapping of the human haploid reference
genome.
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22. LIMITATIONS
• A map generated by genetic technique is rarely sufficient
for directing the sequencing phase of a genome project.this
is for the two reason:
1.the resolution of genetic map depends upon the no
of cross over that have been scored.
2.the genes that are several tens of Kb apart may
appear at the same place in the genetic map
• Genetic map has limited accuracy.
1.presence of recombination hotspots means that
crossover are more likely to occur at some point rather
than at others.
2.physical mapping technique has been developed to
address this problem.
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23. REFERENCES
• U.Satyanarayan:Biotechnology.books and allied (P)
Ltd,Kolkata.
• www.Genome.gov
• www.Wikipedia.comGeneticmaps
• www.sciencedirect.com>topicgenemapping
• www.slideshare.com
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