2. WHAT IS GENOMICS?
Genomics is an area within genetics that
concerns the sequencing and analysis of an
organism’s genome.
It involves the study of all genes at the DNA,
mRNA, and proteome level as well as the cellular
or tissue level.
The term genomics was first coined in 1986 by
Tom Roderick, a geneticist at the Jackson
Laboratory in Maine, during a meeting about the
mapping of the human genome.
3. Genomics is the study of all genes present in an
organism.
By definition, it can be defined as “A discipline in
genetics that applies recombinant DNA,DNA
sequencing methods and bioinformatics to
sequence, assemble and analyze the structure
and function of genomes.”
It includes studies of intragenomic phenomena
such as heterosis, epistasis, pleiotropy and other
interactions between loci and alleles within the
genomes.
4. HISTORY Genomics is a concept that was first developed
by Fred Sanger in early 1970s, who first
sequenced the complete genome of a virus and
of a mitochondrion.
In 1972, Walter Fiers and his research group
became the first to sequence a gene. They
sequenced the gene of Bacteriophage MS2.
In 1995, Hamilton O. Smith and his team
became the first to sequence a genome of a free
living organism – that of Haemophilus influenzae.
5. GENETICS VS. GENOMICS
GENETICS GENOMICS
Genetics is the study of
heredity.
“Gene" refers to a specific
sequence of DNA on a
single chromosome.
Genetics involves the
study of functions and
composition of the single
gene.
Genomics is the study of
the entirety of an
organism’s genes.
“Genome” refers to an
organism's entire genetic
makeup.
Genomics addresses all
genes and their inter
relationships.
6. SUBFIELDS OF GENOMICS
The different research areas of genomics can be
as follows :
1. Structural Genomics
2. Functional Genomics
3. Comparative Genomics
7. GOALS
The main goal of genomics is to :
Sequence the entire genome by cutting it
into small, manageable pieces (fragments).
Assemble the entire genome from the
pieces (fragments).
Understand how gene expression takes
place.
8. WHY TO SEQUENCE GENOMES?
Sequencing genomes helps understand how the
genome as a whole and how the genes work
together to direct the growth, development and
maintenance of an entire organism.
The genome sequence will represent a valuable
shortcut, thus helping to find genes much more
easily and quickly.
9. TECHNICAL FOUNDATIONS
The technical foundation of genomics involves :
Construction of Genomic and cDNA libraries
DNA Hybridization
Restriction-enzyme mapping
DNA sequencing
PCR amplification
10. STEPS IN GENOME SEQUENCING
Break genome into smaller fragments
Sequence those smaller pieces
Piece the sequences of the short fragments
together
GENOME SEQUENCING
APPROACHES
1. Hierarchical shotgun sequencing
-Useful for sequencing genomes of higher
vertebrates that contain repetitive sequences.
2. Whole genome Shotgun Sequencing
-Useful for smaller genomes.
11. HUMAN GENOME PROJECT
The Human Genome Project (HGP) is an
international scientific research project with the
goal of determining the sequence of chemical
base pairs which make up human DNA, and of
identifying and mapping all of the genes of
the human genome from both a physical and
functional standpoint.
HGP was formally founded in 1990 by the US
Department of Energy and the National Institute
of Health and was declared completed on 14th
April,2003.
12. The basic goals of HGP were :
To indentify all the genes and their functions in a
human DNA.
To determine the sequences of 3 million base
pairs the makeup the human DNA.
To develop tools for data analysis.
To obtain physical map of human genome.
To store the information in public databases.
13. BENEFITS & APPLICATIONS
Genomics can be useful in following ways :
It can be used in the field of medicine for early
detection of genetic diseases and its diagnosis
and treatment.
It is also useful in the field of agriculture.
To study evolution through mutation lineages.
In forensic science.