Role Of Genetics In The Welfare Of Human Life
(Muhammad Wajid Javed and Naseem Ahmed)
Before 1900, history of genetics was related to cytology. This owes to “Robert Hooke”, who elaborated various smaller things in a cork section. In 1831, Brown discovered a consistent structure present in a regular way, called “nucleus”. Then Schleiden and Schwann presented “cell theory” (1836-1840) to depict various structures present in the cell and their nature. It was a great contribution towards cell structure. After other contributions, in 1884-1885, four scientists (Hertwig, Kolliker, Weismann (all zoologists) and Strasburger (botanist) derived that heredity matter existed in the nucleus in that material which makes up chromosomes.
After the discovery of Mendel’s work and his laws, Genetics took a progressive turn and revolutionized. Working on this subject is still moving.
Genetics is providing numerous services to humanity in almost every field of life. Thus, its prominent role never be neglected in the welfare and betterment of human lives, in one way or the other. This can be explained on the basis of following points:-
1) The Human Chromosome Complement:-
Correct and accurate number of chromosomes was determined in 1956. In this a sample of blood obtained, cultured and subjected to effects of various chemicals. Application of colchicines, a chemical substance which interferes the mitotic spindle and prevent the movement of anaphase, cells were prohibited in mitotic metaphase. Then, cells were killed and hypotonic solution was applied and slides of sample were visualized. It revealed that there were 23 numbers of chromosomes in both human male and female. After that bending technique (which bought out bands on the chromosomes and gave them permanent stain) was used. This technique has caused a beginning to understand various human disorders based on chromosomes and to cure them.
2) Genes Impacting Survival Of An Individual:-
Various genes are present in every organism/individual, having different character to control. Some genes/alleles control colours, height and other control shape etc. At the same time one gene or allele has the killing action. As metabolism involves various chemical routes, if any one of them is disturbed, may lead to disorder and death. ( e.g. recessive allele for Tay-schs disease kill in infant stage, in human).
Genetics has played a vital role in indentifying such diseases for human survival.
3) Sex Chromosomal Complexities In Human-Beings:-
Various fatal disorders are existed in human due to imbalance of chromosome number. These lead to malfunctioning or death of an individual. Examples are X0(chromosome number is 45, sterile female, Turner syndrome), It is a situation affecting development of sexual and other body parts. Others are XXY(male but almost sterile) etc. Geneticists are trying to control this variation, based on Genetics.
4) Synthetic DNA:-
In mid 1950, Kornberg and associate prepared DNA by in vitro technique. It was found that any performed DNA can be used as primer, that of E. coli or even of a progressive form.
Figure SEQ Figure * ARABIC 1. DNA double helix modal
5) Insect Control:-
a) Induced sterility:-
Different insects harmful to human are controlled by the use various genetic disturbance approaches, such as: irradiation for sterility in bool weevil, medfly. These are susceptible to sterilization.
b) Genetic control of Lucilia cuprina (Australian sheep bowfly):-
It can be controlled by:
i. Genetic manipulation
ii. High level sterility
iii. Release of strains due to chromosome.
c) Genetic control of spider mites:-
This is mainly based upon:
a) Sterile male techniques
b) Use of sterile male
c) Leaving incompatible population based upon reproduction.
6) Animal immunity via genetics:-
Animals generally have helpful and suppressive factors. Their subdivision based on presence antigens or their genetic restriction.(e.g. non specific factors).MLR(Mixed Lymphocyte reaction) suppressive factors has major role in immunity.
7) Useful Output from Bacteria:-
Recombinant DNA technology is producing bacteria in large vessels called, “bioreactors”. These are used to produce various products by replication of genes in them and their active expression. These outputs/products are insulin, growth hormone, hepatitis B vaccine and hemophilia factor VIII etc
8) Encouraging Health Of Plants:-
Various bacterial species are being utilized for increasing health of plants. e.g. bacteria that stays on plant and form ice crystal, these are changed from ice+ to ice- bacteria. Some bacteria also provided with genes that are helping in producing such products which are beneficial against insects attack, e.g. in corn. Similarly sunflowers’ verities that are resistant against “charcoal rot ,also developed by using various techniques based on genetics such as late maturing(Lyng Manchurians) and medium late maturing (KN HD-1)cultivars of sunflower
9) Use of Bacteria for Cleaning:-
Bactria has the ability to decompose a substance. This is utilized for vanishing the harmful effects of oil spills on beaches. Genetically engineered bacteria are doing this job efficiently.
10) Utilization as Biofilters:-
Certain bacteria are used to clean fatal chemicals produced in the industry, in order to prohibit air pollution. Such bacteria are also utilized to catch sulphur from cola after its burning. Thus, helps in the prevention of environmental pollution. After the completion of their tasks, they suicide because of suicide gene inserted in them, so that they may not be problematic in future.
11) Production of Organic Products:-
Because of genetic engineering (a precious gift of genetics), it is now possible to use bacteria for the manufacturing of different organic products (chemicals). Biochemists have identified a strain in bacteria which can be used in production process of phenylalanine; an organic chemical used in formation of aspartame (synthetic sweetener – Nutra sweet). They separated it and used in this process.
12) Extraction of Metals in Mining:-
Several mining companies are using bacteria for the Getting of metals, in mining. Genetic engineering may use to enhance the capability of bacteria to get copper, gold and uranium from less important resources.
13) Plant, Resistant To Pest:-
Different plants such as cotton, corn and potato have gene transferred in them to produce toxins against insects.
14) Herbicide Resistant Plants:-
Soybean has resistant against herbicide. Some corn and cotton plants are both herbicides and insects resistant.
15) More Nutrition and Yield of Crop Plants:-
Under the supervision of geneticists, scientists are working to enhance and improve the protein, starch, oil and amino acid contents of crop plants. Various agribusiness companies and firms are producing high quality and good yield based hybrid verities of corn, rice and maize. Hybrid plants are more productive than that of normal commercial cultivars of crops. Development of such high yielding verities is the necessity of the world to face the future food crises. This may also be done by the following aspects:
a) Changing the stomata in such a way that their efficiency to take and use CO2 is enhanced.
b) Encouraging efficiency of RuBP
c) Introducing C4 pathway in plants, which is efficient than that of C3
16) Producing useful products by plants:-
Because of genetics, it is now possible to obtain products which are beneficial to human-beings. e.g. a plant known as “mouse-eared cress” is engineered genetically to produce biologically disposable plastic (polyhydroxy butyrate)in their cell organelles. Plants are also engineered to produce human hormone , antibodies and clotting factors in their seeds. An antibody developed by soybean, can be used as cure of genital herpes. Antibodies based on plant origin are inexpensive and less susceptible to attack by pathogens.
17) Genetically Modified Animals:-
Genetically Modified (Transgenic) Animals are produced by the incorporation of foreign gene into their cells(eggs) in the presence of DNA and silicon-carbide needles. After fertilization these cells results in the production of “Transgenic Animals”. There are various beneficial implications associated with them:-
a) Bovine growth hormone
b) Growing of larger animals such as sheep, fishes, cows and rabbits
c) Transgenic animals are also used to produce different medicines
d) Obtaining of therapeutic and diagnostic proteins that are produced in their milk
e) Drugs may also be produced to cure cystic fibrosis, blood diseases, cancer and other fatal disorders
f) Antithrombin III is also produced by different goats to prohibit blood clotting during operations
g) Producing biotechnological outputs in milk. Eggs of these animals (mammals) are infected with gene and then transplanted into female. When off springs mature, products are excreted in their milk
Scientists have been able to genetically engineered mice to produce human growth hormone in their milk. Now they are striving for the production of these hormones in urine instead of milk because it is a better agent leading to more production of these hormones. It is because of the reason that milk is produced by female only and at maturity while urine is excreted by both male and female and also from their immature stages.
In short, genetics has played a vital and splendid role in making human lives easy, glorious and satisfactory.
Muhammad Wajid Javed is student of B.Sc. (Hons.) Agriculture (Department of Agricultural Entomology, University of Agriculture, Faisalabad, Pakistan.) and also affiliated with Agrihunt as an Author.
Mob. No: 0313-7070047
Mob. No: 0346-5235161