GOLDEN JUBILEE
OF A LANDMARK DISCOVERY
V.K.
Subramanian*
One often wonders
how life began on earth. Plato had suggested the origin of life
as a divine creation while Aristotle believed in the existence
of spontaneous generation. Most biologists of the 17th and 18th
centuries believed that all living beings were divinely created
in their present forms. But a scientist called Linneaus felt that
some organisms were related to each other. The first scientist
to work out the theory of evolution was Lamarck in 1801 who suggested
that all species have descended from other species. He believed
that organisms were constantly increasing in complexity due to
the shaping power of environment, i.e. the universal creative
principle. However, Darwin’s concepts of evolution, led him to
believe that the cumulative effects of natural forces had produced
continuous change in the course of the earth’s history. Scientists
have studied and compared different forms of life in order to
establish this evolutionary relationship - a fundamental property
of life. However, as regards the origin of life, the uniform experience
as per David Hume is that it takes an intelligent agent to generate
information, codes and messages. As a result, it is reasonable
to infer that there was an intelligent course of the original
DNA code. The DNA and written language both exhibit the property
of specified complexity. Since we know that an intelligent course
produces written language, it is legitimate to believe an intelligent
cause as the source of DNA - the deoxyribonucleic acid.
The DNA molecule
has been one of the greatest scientific developments of the 20th
century. The DNA is the chemical agent that encodes instructions
for building and replicating almost all living beings. Watson
and Crick, who are credited with DNA’s discovery fifty years ago,
could never have imagined that it would become a turning point
for biological science in the 21st century.
The Watson and Crick
model explains that DNA possesses impressions and structural complexity.
Not only did the model helix structure presuppose that DNA constituted
an extremely long, high molecular weight structure but it also
implied that the sugar molecules in the sugar phosphate backbone
would allow any four nucleotide bases to attach to them. The chemical
freedom suggested that the sequencing of bases would defy reduction
to any rigidly repeating pattern, thus allowing DNA to possess
an impressive potential for variability and complexity. With the
discovery of the structure of DNA, the direct manipulation of
genetic traits became a possibility. One of the first discoveries
about DNA was the inherent ability to be copied. It was astonishing
to find that all living organisms including bacteria are made
of the same components and their genetic code is the same. DNA
can now be treated and manipulated like simple building blocks.
DNA pieces can be taken out and replaced with DNA from any living
being. This transfer of individual DNA pieces or genes is the
basis of genetics and genetic manipulations.
In the developed
world, the greatest number of modern biotechnology applications
are in health care, where they offer new hope to patients with
AIDS, genetically inherited diseases, diabetes, influenza and
various forms of cancer. Biotechnology - based processes are now
being used routinely in the production of most new medicines,
diagnostic tools and medical therapies.
Agricultural Applications
New developments
in agricultural biotechnology have contributed to increasing crop
productivity, primarily reducing the costs of production through
efficient farm practices and reduction in the use of pesticides
and herbicides. In global terms, increase in world food production
has more than kept pace with the rise in global population to
date. Although the world agricultural growth rate has decreased
from 3 per cent in 1980’s to 2 per cent in the last decade, the
aggregate projections show that world food supply will continue
to outpace world population growth at least till 2020. Biotechnology
holds the key to increasing the yield of staple crops from currently
cultivated land, while preserving the land’s ability to support
continued farming.
Biotechnology can
expedite the development of new varieties and help enhance marginal
crops like millets, banana, grain legumes, cassava and sweet potato
which are also important staples in the developing world. Introducing
genes that increase available iron levels in rice three-fold is
a potential remedy for iron deficiency. Modern biotechnology also
offers effective techniques to address food safety concerns. Biotechnological
methods can be used to reduce the time needed for detecting food-borne-pathogens,
toxin and chemical antibodies. Microorganisms produced using DNA
techniques are effective in monitoring food production systems
for quality control.
Human Applications
DNA underlines every
aspect of human life, both in function and dysfunction. Biomedical
methods are now raised to produce many proteins for pharmaceutical
and other specialised purposes. Microorganisms are modified to
make insulin. The products of modern biology include artificial
blood vessels from collagen tubes coated with a layer of the anticoagulant
heparin.
DNA fingerprinting
is the process of cross matching two strands of DNA. It has become
one of the most powerful and widely known applications of biotechnology
today. Paternity determination is possible due to this powerful
technique. DNA testing is also used to determine closely-related
fossils’ samples from different geographic locations and geological
areas. The results shed light on the history of human evolution
and the manner in which their ancestors settled in different parts
of the world.
The most far-reaching
potential application of specialised human cells called stem cells
is the generation of cells and tissues that could be used for
"cell therapies".
Genomic data and
technologies are expected to make drug development faster, cheaper
and more effective. Most drugs today are based on about 500 molecular
targets, genomic knowledge of genes involved in diseases, disease
pathway and drug response sites. These can lead to the discovery
of thousands of new drug targets. Pharmacogenomics will help speed
up the design of clinical trials and bring the drugs to the market
faster.
The applications
of biotechnology are so broad and the advantage so compelling
that virtually every industry is using this technology. Developments
are underway in areas as diverse as pharmaceuticals, diagnostics,
textiles, aquaculture, forestry, chemicals, household products,
environmental cleanup, food processing and forensics, to name
a few. Biotechnology is enabling these industries to make newer
and better products, often with greater speed, efficiency and
flexibility. Biotechnology holds out significant promise to the
future. A certain amount of risk is associated with some technologies.
But that is part of scientific research. One can always address
the risks scientifically to remove fear, if any, from the public
mind.(PIB Features)
*Information
Officer, PIB, Delhi
