FOOD BIOTECHNOLOGY

TOPIC- GENE CLONING- STEPS AND

TECHNIQUE INVOLVED IN GENE

CLONING.

SUBMITTED BY,

S.SHOBANA,

PERIYAR UNIVERSITY,

SALEM.

INTRODUCTION:

Cloning means using asexual reproduction to obtain

organisms that are genetically identical to one another,

and to the ‘parent’, of this contrasts with sexual

reproduction, where the off spring are not usually

identical.

It is worth stressing that clones are only identical

genetically. The actual appearance and behavior of the

clones will be influenced by other factors such as their

environment.

This applies equally to all organisms from bacteria to

humans.

THE BASIC STEPS IN A GENE CLONING EXPERIMENT ARE AS

FOLLOWS:

A fragment of DNA, containing the gene to be cloned, is

inserted into a circular DNA molecule called a vector, to

produce a chimera or recombinant DNA molecule.

The vector acts as a vehicle that transports the gene into

a host cell. Which is usually a bacterium, although other

types of living cell can be used.

With in the host cell the vector multiplies, producing

numerous identical copies not only of itself but also of

the gene that it carries.

When the host cell divides, copies of the recombinant

DNA molecule are pared to the progeny and further

vector replication takes place.

After a large number of cell division, a colony or clone

of identical host cells is produced. Each cell in the clone

contains one or more copies of the recombinant DNA

molecule, the gene carried by the recombinant molecule

is now said to be cloned.

CLONING:

A clone of consist of all the cells derived through

mitosis from a single cell and the process of

obtained a clone is called cloning. Therefore, all the

cells of a clone are expected be identical with each

other in their genotype and karyotype (chromosome

constitution) and other attributes, except for the

changes that may arise a fresh during and after

cloning.

Coning is based on single cell separated from

tissue and cultural in a manner to allow separate

recovery of the cell mass derived from them.

THE USE OF VECTORS AS CLONING VEHICLES:

Vectors can be introduced into suitable host cells, where

they replicate using the host’s enzyme.

A segment of foreign DNA which has been cloned into

vector is therefore amplified along with vector DNA.

Large amounts of the desired foreign DNA are therefore

produced. The vast majority of vectors are plasmids, the

remainder consisting of those based on bacteriophase

lambda and M13.

The major requirement of all vector of replication for a

given host cell in order that they may replicate

autonomously.