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DNA and Genetic Engineering—The Beginning of Modern Botechnology

DNA and Genetic Engineering—The Beginning of Modern Botechnology  
    The science of genetics was transformed by the discovery of DNA (deoxyribonucleicacid), which carries the hereditary information in the cells. The chemical DNA had already been discovered in 1869 by Fricderich Miesdwr but was not taken seriously as the chemical basis of genes until the early 1950s. Two scientists, Francis Crick and James Watson along with Rosalind Franklin, in 1953. discovered that the DNA structure was a double hchx: two strands twisted around each other like a spiral staircase with bars across like rings. The structure, function, and composition of DNA are virtually identical in all living organisms—from a blade of grass to art elephant. What differs—and makes each creature unique—is the precise ordering of the chemical base in the DNA molecule. This gave scientists the idea that they might change this ordering and so modify lifeforms. Marshall Nirenberg and H. Cobind IChorana carried out the deciphering of the genetic code In 1961.
     Soon scientists and industrialists were seeking to alter the genetic make-up of living things by transferring specific genes from one organism to another. They could now modify lifeforms by altering the hereditary material at the molecular leveL Walter Gilbert carried out the first recombinant DNA experiments in 1973. and the first hybridomas created in 1975. The production of morioclonal antibodies for diagnostics was carried out in 1982, and the first recombinant human therapeutic protein, insulin (humulin), was produced in 1982. In 1976, the U.S. company Genentech became the first biolech company to develop technologies to rearrange DNA. Commercial uses of recombinant-DNA-assisted biotechnology include the development of interferon, insulin, and a number of genetically-modified crop plants such as the high-solids-processing tomato that has 20% less water. Transgenic animals have been cnated such as the unfortunate onco-mou. designed to develop cancer ten months after birth to study cancer.
     Companies have been assisted and encouraged in their research by the 1980 ruling of the US. Supreme Court allowing genetically-engineered microorganisms to be patented. This means that virtually any hfeform on this planet can theoretically become the private property of the company or person who ‘creates’ it. One of the greatest threats of the new biosciences is that life will become the monopoly of a few giant companies.
    An estimated 600 pharmaceutical companies worldwide are conducting research and developmL’nt into genetically-engineered products. Mistakes aie bound to happen. And with something so powerful as gen&tic engineering, one mistake could have profound and wide-ranging effects. The whole gene revolution is on the verge of becoming the private property of a few multinationals must impose tough controls on the genetics supply industry and work to make sure that the new techniques are In the service of the global community

Milestones in the History of Biotechnology
5000 BC Jndus and Indo-Aryan civilizations practiced biotechnology to
produce fermented foods and medicines and to keep the
environment dean.
4000 BC Egyptians used yeasts to make wine and bread.
1750 BC The Sumerians brewed beer.
250 BC The Greeks used crop rotation to maximize crop fertility.
1500 AD The Aztecs made cake from spirulina.
1663 Robert Hook first described cells.
1675 Microbes were first descnbed by Anton Van beuwenhock.
1859 Darwin published his theory of evolution in ‘The Origin c’Species.’
1866 Gregor John Mendel published the basic laws of genetics.
1869 DNA was isolated by Friederich Miescher.
1910 Genes were discovered to be present in chromosomes.
1917 The term ‘biotechnology’ was used to describe fermentation
           technology

1928  The first antibiotic. penicillin, was discovered by Alexander
          Flemming.
1941 The term ‘genetic engineering’ was first used.
1944 Hereditary material was identified as DNA.
1953 Watson and Crick proposed the double helix structure of DNA.
1961 Deciphering of genetic code by M.Nirenberg and H.G. Khorana.
1969 The first gene was isolated.
1973 The first genetic engineering experiment was carried out by
          Walter Gilbert.
1975 Creation of the fIrst hybridomas.
1976 The first bioteth company.
1978 World’i first ‘test-tube baby.’ Loulse Brown, was born through in
          vitro fertilization.
1981 The first gene was synthesized. The first DNA synthesizer was
          developed.
1982 The first genetically engineered drug, human insulin, produced
         by bacteria, was manufactured and marketed by a US company.
         Production of the first monoclonal antibodies for diagnostics..

1983 The first transgenic plant was created—a petunia plant was
          genetically engineered to be resistant to Aureomycin, an antibiotic.
1983 The chromosomal location of the gene responsible for the genetic
         disorder, Huntington’s disease, was discovered leading to the
          development of genetic screening test.
1985 DNA fingerprinting was first used in a criminal investigation

1986  The first field tts of genetically-engineered plants (tobacco) were
          conducted. Chymosm. an enzyme used in cheese making,, became 
           the first product of genetic engineering to be introduced into the food  
            supply.
1990 Human genome project was launched.
1990 The first human gene therapy trial was performed on a
          four-year-old girl with an immune disorder.
1991 The gene implicated in the inherited form of breast cancer was
         discovered.
1992 Techniques for testing embryos for inherited diseases were
         developed.
1994 First commercial approval for transgenic plant by the U.S.
         government.
1995 First successful xenotrans plantation trial was conducted,
          transplanting a heart from a genetically  engineered pig into a
           baboon
1996 First commercial introduction of a ‘gene chip designed to rapidly
         detect variances In the HIV virus and select the best drug
          treatment for patients.
1996 Dolly, the sheep was cloned from a cell of an adult sheep.
1998 Embryonic stem cells were grown successfully, opening new
         doors to coli- or tissue-based therapies.
         A US. company announced the successful cloning of human
         embr’1onic cells from an adult skin cell.
1999 Chinese scientists cloned a giant panda embryo.
1999 Indian scientists and companies started producing recombinant
          vaccines, hormones, and other drugs.
2002 The draft of human genome sequence was published.

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