Wednesday, January 30, 2008

The Unexplained becomes Explained-- An Essay

The Unexplained becomes Explained

Let There be light……….and, this was the beginning of the creation processof this wonderful universe. So vast, unbound, unexplored a mystery thatsurvived and surpassed anything, beyond compare. Truth is stranger thanfiction, but the undefying truth is the presence of life only on thisplanet named Earth. The miracles of man-made inventions only complementthe creator’s own. Genetics is undoubtedly one such a miracle that has andcontinues to explore the unexplored vistas of mysterious realms. The listis endless, be it an invention of genetic forces or adding values to thefood-consumption. Taking this factor into consideration, this essay wouldtake up the task of highlighting on three such marvels.

The discovery of living cells by Robert Hooke provided naturalists withnew vistas on life. Perhaps it was the excessive enthusiasm of this newworld, of the very small that give an ascend in the development ofgenetics -the field of genes and human kind. Developmental genetics hadalready grown its roots during 883-859 B.C during the reign of kingAssurnasirapalli II when scientists of his kingdom had started artificialpollination of date palms. Today the major crops have undergone extensivegenetic alterations to increase their yields and provide desirable traits,such as disease and pest resistance and special nutritional characters.Several million people in the world, most of them in Asia, go hungry eachday. Imagine a genetically engineered rice crop that could potentiallyreduce this number significantly, and provide resistance to diseases.Genetic modification of food has been going on for quite some time but itwas thirty years ago when a man named Norman-Borlaug won the Nobel PeacePrize for his development of high-yielding wheat varieties that helpedfeed people in developing countries. In 1999, Swiss and German scientistsannounced the development of a golden-rice genetically engineered toproduce beta-carotene, a substance that the body can convert to Vitamin A.The new rice was quickly heralded as a miracle cure for vitamin Adeficiency (VAD),a condition that afflicts millions of people especiallychildren and pregnant women. Severe VAD causes partial or total blindness;less severe deficiencies weaken the immune system. Hence Golden Rice todayhas proved to be very helpful in overcoming VAD.

DNA, with its gentle double-stranded spiral, is among the most elegant ofall the biological molecules. But the double helix is just not a beautifulstructure but it also give DNA incredibility and permanence, asillustrated by the great discovery of the Ice Man. On September 19,1991,German hiking in the Tyrolean Alps near the border between Austria andItaly spotted a corpse trapped in glacial ice. Moreover a copper-axe,dagger, bow and a quiver with 14 arrows were found alongside the body. Thebody was sent to the University of Innsbruck where it was refrozen andsubjected to scientific studies to establish his ethnic origin.Radioactive dating indicated that the Ice Man was approximately 5000 yearsold, who was shot in the chest with an arrow and died soon thereafter,after which the body became dehydrated in the cold air and remainedcovered by ice till 1991. Under sterile conditions, the investigatorsextracted DNA from samples and conducted polymerase chain reactions toamplify a very small region of his mitochondrial DNA a million fold anddetermined the base sequence of this amplified DNA and compared it withthe mitochondrial sequences from present-day humans.

This analysis revealed that Ice Man’s mitochondrial DNA sequencesresembled those found in the present day Europeans living north of theAlps. Together, radiocarbon dating, the artifacts, and the DNA analysisall indicate that the Ice Man was a Neolithic hunter. The Ice Man’s DNApersists and carries his genetic instructions even after the passage of5000 years is a testimony to the remarkable stability of the DNA and anachievement in the field of Genetics.Genetics has stretched its hands so far that today we can even imaginesituations where an extra set of eyes might come in handy, just like thatof Lord Shiva’s. It would be very unlikely for all of these structures todevelop at a site where eyes really don’t exist. Nevertheless, in 1995 agroup of geneticists succeeded in genetically creating fruit flies withextra eyes on their wings, legs and antenna. How was this amazing featcompleted?

This story of creating extra eyes actually began in 1915 when Mildred Hogediscovered a mutant fly with small eyes due to a recessive mutation in agene called eyeless. The product of the normal allele of this eyelesslocus is required for the actual development of fruit-fly-eye. It was in1993 when Walter Gehring and his collaborators genetically engineeredcells that expressed the eyeless gene in parts of the Drosophila where thegene is not normally expressed. When these flies hatched; they had hugeeyes on their wings, antenna and legs. They were not just normal tissuesthat resembled eyes but complete eyes with cornea, cone cells andphotoreceptors. However one drawback was that the flies could not use themto see because they were not connected to the nervous system. Todaygeneticists have found out that the eyeless gene has it counterparts inmice and humans also. The amplification in the developments of geneticshas been increasing day by day.Its not very far when a day would come when we would have 3 eyes forperception and 2 brains for powerful thinking. That’s the power ofGenetics.

Genetics has indeed opened up a deep treasure to be exploitedand explored. The instances --- in this essay are just a tipin the iceberg. A time would dawn when the unexplained wouldbecome explained and when we would come into Light fromDarkness, Into Knowledge from Ignorance and into Immortalityfrom Mortality. Till lead kindly light….!

30th Jan, 2008

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