History of genetic engineering
Humans have been altering the genomes of species since long back. The term genetic engineering was first coined in a Science fiction novel “Dragon’s Island,” by its author Jack Williamson in 1951. Then after some years, Watson and Circk discovered the DNA structure.
The first recombinant DNA was constructed by Paul Berg in 1972. Also, Herbert Boyer and Stanley Cohen performed gene transfer experiments in the same year.
In 1974, Rudolf Jaenisch had created genetically modified mice, the first time in the history of genetics. In 1976, he also created the genetically designed tobacco plant species.
The time period between 1960 and 1990 saw the innovation of many new techniques like ligation, restriction digestion, and PCR. All these new techniques bolstered the development of genetic engineering.
What is genetic engineering?
It is the process of changing genes by using biotechnology methods. It allows the transfer of genes within the organism or across it. With the help of genetic engineering method of cross-hybridization, today humans are able to grow economically valuable plants. Genetic engineering can be used for the following purposes:
- Construction of genetically modified plant species.
- Abiotic and biotic stress resistant plant species.
- Economically important plant species
- Commercially valuable organism
- For the production of therapeutic drugs
- Prevention of genetic abnormalities.
- Genes of interest- It is a DNA sequence which we want to insert in our target cell.
- Vector- It is an artificial vehicle that carries the genes of interest to the targeted cell.
- Target cells- It is the destination where we want out gene of interest to reach.
What are the types of Genetic engineering techniques?
Some physical methods create the artificial DNA molecule under this technique. The gene of interest inserts into the plasmid vector which is used for the gene transfer experiment.
Delivery of gene
In this technique, we insert the gene of interest into the host genome. Methods that come under this technique are liposome-mediated gene transfer, Electrophoration, solicitation, and transposon-mediated gene transfer.
Editing of gene
This technique gives the ability to edit the gene for transfer. The unwanted DNA sequence is removed or a new gene can be placed into the host genome. Some of the gene editing tools are namely- TALEN, CAS9, and ZFN.
What are the processes of genetic engineering?
- Step-1:Selecting and isolating the candidates gene
- Step-2:Selection and construction of plasmid
- Step-3:Gene transformation
- Step-4: DNA insertion into the host genome
- Step-5: Confirmation of insert
There are wide applications of genetic engineering. Today it has found its use for medicines, agriculture, genetic research, genetically modified organisms, therapeutic drugs and for crop improvement.
Talking specifically for the crops, the growers generally use recombinant DNA technology. Some of them are
- Virus resistance
- Herbicide resistance
- Delayed fruit ripen
- Pollen control
- Altered oil content