Genetic Engineering

Introduction

Genetic engineering deals with the detailed knowledge of gene, its molecular structure and nature as well the ability to manipulate cells of higher plants or animals to the different vector DNA. In this technique DNA of species in inserted into the DNA of vector such as plasmid, cosmid, virus, etc. In this technology terms such as “gene surgery”, “gene manipulation”, “gene therapy”, “gene transplantation”, etc. commonly used.

Genetic engineering has brought a great revolution in the sector of agriculture. This technique has brought different improvement in the plants which are able to good in both quality and quantity. This technique is able to produce different plants which are diseases resistant, has all the required nutrients, resistance to fungal, bacteria and virus. This technique has done great work in the field of medical science too.

Application of genetic engineering in the field of agriculture

Genetic engineering has done a great improvement in the field of agriculture. With the help of genetic engineering new plants with better quality and quantity can be produced. New and virus free plants can be produce with the help of genetic engineering. Some other applications of the genetic engineering are describe below:

1. Creation of diseases resistant plants: The manipulation of the gene of one species to another species may produce the varieties that are diseases resistant as well as pests. Different diseases resistant genes can be manipulated in the gene of other species as well as cloned to produce the diseases resistant plants. For examples; Bacillus thuringiensis is a bacterium which can resist against the pest on the maize and rice. If the Bt gene from the bacterium is isolated and manipulated in the gene of maize or rice and cloned, as a result pest free maize or rice can be obtained. Golden rice is one of the best example of the progress of genetic engineering.
2. Bio-fertilization: Bio-fertilizer is the fertilizer prepared by the biologically active products which are capable to improve the fertility of soil. Bacterium like Rhizobium is symbiotic and found in soil which form nodules in the roots of legume plants .It helps the plants by fixing the free nitrogen of atmosphere to the soil in the form of nitrates. The free nitrogen of the atmosphere cannot be utilized by the plants; it is the great help for them. They have capacity of fixing the free atmospheric nitrogen as well as exudates nitrogenous compound into the leave cavities. Those leaves can be the best bio-fertilizer.
3. Increase the protein content: Seeds of many plants are the main source of the protein for the both human beings and animals. Different pulses are the major source of protein as they store the protein, but they contain limited amounts of amino acid which are important for the human beings. Most of the cereals lack of the lysine whereas legumes are lack of sulphur amino acid. This technology can produce the clone of the different cereals and legumes which store the required amount of protein for human. Such as the genes encoding the French bean protein, phaseolein, has been expressed in sunflower.
4. Creation of transgenic animals: Transgenic is defined as the animals are carrying as foreign genes which are inserted in their germ lines. These sorts of animals are capable of transferring the gene to their offspring as well as can inherit.

Cloning

It is the process of creating the exactly the same or carbon copy of the single parents. A clone is defined as the offspring which is exactly same copy of the single parent. In simple word it the copy paste of the single parent. Or the offspring obtained artificially by the growing the cell or the different parts of the parent. Monizygotic, identical twins are cloned in case of the human beings. Dolly sheep is most re-known example of the cloning.

Types of cloning

• Microbial cloning
• Cell cloning
• Plant cloning
• Animals cloning

Possible dangers of genetic engineering

Genetic engineering has many advantages. However on the process of gene manipulation is result worth or harmful one. Some of its disadvantages have been are discussed below:

1. By accidently during the gene manipulation it result the new harmful diseases or organism containing fatal genetic elements.
2. During the creation of the useful organisms, it may result the drug resistant germs which may cause the various diseases which do not have the cure.
3. During the process introducing the genes like viral cancer into the bacteria through the plasmids, it may result harmful gene into the man which can infect human.
4. The serious ecological problems which are caused by the hybrid genomes, its nature is still unknown.

To over view or to observe the problems created by the genetic engineering, in 1976 the US National Institute of Health (NIH) established an advisory committee. It mostly work for the evaluation of the potential of the biological and ecological hazards of the recombinant DNA molecules.

Advances of genetic engineering

Genetic engineering has great scope in the present world. Some of its area of recent development are described below:

Human Genome Project

In 1990, the human genome an international project was started with the objectives of mapping the different types of chromosomes. Prof. Watson was the first person to headed this project. This project was about the preparation of a separate geenetic linkage map and a physical map of the different cheomosomes. It is believed that there are 30,000 genes in human genome and about 200 genes are assigned at each chromosome. Every person has different chromosomes which can be recognized by distinctive banding pattern of each chromosome. Some of the objectives of this project are as follows:

• For the development of the human genome mapping and also their characters.
• To settle the different issues which can be arise against this project.
• For the development of the gene therapy technique in human.

Genomics

The branch of genetics which deals with the study of the organisms in terms of gemones . Genomics is defined as the branch of genetics which deals with study of the genome mapping, gene sequencing and gene functions. Genome also can be defined as “the total number of genes contained in one haploid set of chromosome of a diploid organism.” There are 100 millions cells in human body and over 260different types. Human DNA consists of 23 pairs of different chromosome. Extra DNA present in the mitochondria is transfer from the mother’s chromosome.

Gene therapy in human

1. Gene therapy means the technique of replacing the defected gen by the normal gene. This technique can replace the defected gene of human with the normal and healthy gene. This technique can use for the treatment of the genetic diseases also.
2. The disease caused by the defect of the gene for the enzymes adenosine deaminase (ADA) is known as Severe Combined Immuno-deficiency (SCID).This is caused due to lack of the gene which can produce ADA. T-lymphocytes of the person suffering from SCID are functionless. Due to the functionless T-lymphocytes they are unable to respond against the pathogens. Such diseases can be cured by the technique of enzymes replacement gene therapy.

DNA fingerprinting

DNA fingerprinting is the technique which can identify the relationship among the persons with the patterns of DNA fragments obtained in restriction analysis of human DNA. In 984 this technique was developed by the British genetist Alec Jeffreys. The DNA fingerprints of every person in the world is different from each other.

Applications of DNA fingerprinting

• This technique is use for the detection of the child for their true biological parents. The DNA band of the parents should be match with their child.
• This technique is highly applicable for the detection of the criminal involve in different criminal activities with the help of their hair, nail, blood, skin and other body parts.
• This technique is used for the detection of the unidentified dead body.
• This technology is applicable for the identification of the social group to rewrite the evolution.

Transgenic

Transgenic organisms are those organisms which contain a DNA segment from different species. These sorts of animals or plants are made artificially using genetic engineering. So, they are also called genetically engineered organisms. Scientists have created many different transgenic plants and animals. Some of them are mentioned below:

• Production of human insulin from bacteria.
• Golden rice containing vitamin A
• Production of the transgenic animals like cow, sheep and goat by inserting human gene for the production of antihaemophilic factor, growth factor and other.
• Different crops have been produced which are virus and fungus free.
• Transgenic pig which is created by inserting human gene o that it can carry human antigene. Due this it possible to transplant different organs likes kidney, heart, etc. form transgeneic pig to human safely.

Refrence

Arvind K. Keshari,Kamak K. adhikari. A Text Book of Higher Secondary Biology. Kathmandu: Vidyarthi Pustak Bhandar, 2014.

Agrawal, sarita. principle of biology. 2nd edition . kathmandu: Asmita book Publication, 2068 ,2069

Mehta, Krishna Ram. Principle of biology. 2nd edition. kathmandu: Asmita, 2068,2069.

Jorden, S.L. principle of biology. 2nd edition . Kathmandu: Asmita book Publication, 2068.2069.