Science is a creature that continues to evolve at a much higher rate than the beings that gave it birth. The transformation time from tree-shrew, to ape, to human far exceeds the time from an analytical engine, to a calculator, to a computer. However, science, in the past, has always remained distant. It has allowed for advances in production, transportation, and even entertainment, but never in history has science be able to as deeply affect our lives as genetic engineering will undoubtedly do.
By understanding genetic engineering and its history, discovering its possibilities, and answering the moral and safety questions it brings forth, the blanket of fear covering this remarkable technical miracle can be lifted. The first step to understanding genetic engineering and embracing its possibilities for society is to obtain a rough knowledge base of its history and method. The basis for altering the evolutionary process is dependant on the understanding of how individuals pass on characteristics to their offspring. Genetics Essay achieved its first foothold on the secrets of nature’s evolutionary process when an Austrian monk named Gregor Mendel developed the first “laws of heredity.
” Using these laws, scientists studied the characteristics of organisms for most of the next one hundred years following Mendel’s discovery. These early studies concluded that each organism has two sets of character determinants, or genes (Stableford 16). For instance, in regards to eye color, a child could receive one set of genes from his or her father that were encoded one blue, and the other brown. The same child could also receive two brown genes from his or her mother. The conclusion for this inheritance would be the child has a three in four chance of having brown eyes, and a one in three chance of having blue eyes (Stableford 16). Genes are transmitted through chromosomes which reside in the nucleus of every living organism’s cells.
Each chromosome is made up of fine strands of deoxyribonucleic acids, or DNA. The information carried on the DNA determines the cells function within the organism. DNA discovery is attributed to the research of three scientists, Francis Crick, Maurice Wilkins, and James Dewey Watson in 1951. They were all later accredited with the Nobel Prize in physiology and medicine in 1962 (Lewin 1). “The new science of genetic engineering aims to take a dramatic short cut in the slow process of evolution” (Stableford 25).
In essence, scientists aim to remove one gene from an organism’s DNA, and place it into the DNA of another organism. This would create a new DNA strand, full of new encoded instructions; a strand that would have taken Mother Nature millions of years of natural selection to develop. Isolating and removing a desired gene from a DNA strand involves many different tools. DNA can be broken up by exposing it to ultra-high frequency sound waves, but this is an extremely inaccurate way of isolating a desirable DNA section (Stableford 26). A more accurate way of DNA splicing is the use of “restriction enzymes, which are produced by various species of bacteria” (Clarke 1). The restriction enzymes cut the DNA strand at nucleotide bases both upstream and downstream from the gene to be transfered.
Now that the desired portion of the DNA is cut out, it can be joined to another strand of DNA by using enzymes called ligases. The final important step in the creation of a new DNA strand is giving it the ability to self-replicate. This can be accomplished by using special pieces of DNA, called vectors, that permit the generation of multiple copies of a total DNA strand and fusing it to the newly created DNA structure. Another newly developed method, called polymerase chain reaction, allows for faster replication of DNA strands and does not require the use of vectors (Clarke 1).
In nature, most organisms copy their DNA in the same way. The PCR mimics this process, only it does it in a test tube. When any cell divides, enzymes called polymerases make a copy of all the DNA in each chromosome. The first step in this process is to “unzip” the two DNA chains of the double helix. As the two strands separate, DNA polymerase makes a copy .
