Headline March 15, 2016/ ''' GENETIC ENGINEERING '''


HARVARD UNIVERSITY   - around 1980s-  first announces that it will establish a  genetic engineering  company to reap-

The financial rewards of techniques developed in its laboratories    -then under pressure, changes its mind rather quickly.

A researcher accidentally uses the wrong virus in a genetic experiment   -a risky, African-insect virus.    -and his work is shut down. A noted scientist comes under heavy criticism for conducting gene splitting experiments on humans.

DNA tinkering, once a distant science, in 80s, is now exploding on the front pages of our newspapers. The headlines talk mostly of promising advances.

Gene-splicing   [also known as recombinant DNA]   has lead to low-cost insulin for diabetics, enzymes to dissolve blood clots, the transplanting of genes to fight genetic diseases, and may soon make possible mass production of interferon to fight infection.

But the torrent of research breakthroughs  -and commercial applications -has not drowned out memory that these techniques were born less than a decade ago in a storm of controversy. 

Fears were expressed then that tinkering with bacterial DNA could one day produce an  ''Andromeda Strain'' of lethal microorganisms, able to burst out of labs and plague mankind with new diseases.

These concerns led, in 1974, to a temporary halt in certain gene splicing work, called by the leading researchers themselves. Only after scientists agreed on stringent guidelines   -including a ban on research into poisonous or antibiotic immune bacteria except in insulated labs  -did such work resume.

A surge of discoveries has come in the last five years, and most scientists in the field believe that the techniques in practice are safe. But some still fear that the resulting commercial applications, involving thousands of new workers, may erode the new safeguards.

''Recombinant DNA has been so productive in basic research and marketable products that issues of safety have been downplayed.'' claims Harvard Medical School geneticist Jonathan Beckwith.

The discoveries making genetic wizardry possible came together in California in the early 1970s. Scientists knew that hereditary traits in plants and animals are controlled by long, chainlike molecules called DNA [deoxyribonucleic acid] and found in every cell's nucleus.

But even after scientists had deciphered the chemical code by which DNA gives genetic instructions, the individual genes of heredity still seemed inaccessible to manipulation.   

A DNA molecule looks like a long, twisted braid of computer tape and gene is just a minute section of instructions on that tape. 

The DNA tapes in one human cell would stretch several feet if straightened out; but, awkwardly wadded up inside a cell's nucleus, they form specs so tiny they can barely be seen with a light microscope.

Cutting and Pasting. Scientists turned to simpler organisms to study their less less complex genes......-first to the early cultured  E. coli  bacterium, a normally harmless one-cell germ that lives in the human gut.

Then they found that some bacteria like E. coli have smaller, simpler, ringlike bits of DNA distinct within the cell body.

In 1972, Stanley N. Cohen of Stanford University developed a way of these tiny rings of DNA [called plasmids] from the bacterium and sticking them inside another. In the new host, a DNA ring became a part of the genetic machinery, and when the bacterium multiplied, so did the alien DNA.

The next advance was a technique for cutting a DNA ring so that a new gene could be inserted in it. Imagine a DNA ring like a chain of paper dolls. The trick is to cut the chain, paste a new gene strip into it and glue it all back together.

In the early 1970s,  Herbert W. Boyer of the University of California, San Francisco, found a technique for doing this with restriction enzymes, proteins that recognize specific sites in a DNA chain and cause the chain to break apart there.

Scientists could now extract a simple ring of of DNA from a bacterium, use a restriction enzyme like scissors, to cut the ring, insert a human gene, then stick the ring back into a bacterium. 

Bacteria multiply rapidly. Within a few hours there would be thousands, each-containing the human gene, as well as the products the gene creates.

For example, when scientists stick the human gene that makes insulin into a bacterial DNA ring, thousands of microorganisms turn up, each loaded with insulin. 

Suddenly, a valuable hormone that previously could be extracted only from pigs, sheep and cattle, might be produced from a new source. 

The Honour and Serving of the cutting edge  Advance Sciences Research continues. Thank Ya all for reading and sharing.

With respectful dedication to all the Research Scientists, and all the Research Universities of the world. See Ya all on !WOW!  -the World Students Society :

''' Gene Makers '''

Good Night and God Bless

SAM Daily Times - the Voice of the Voiceless


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