Category Great Scientific Discoveries

          Poliomyelitis or polio is a viral infection that can cause paralysis. It remained a widespread threat until the US physician Jonas Salk developed polio vaccine. It was first successfully used at a trial in 1952 and the Salk vaccine finally received approval in 1955 after further trials.

          The more commonly used vaccine against polio that is administered orally was developed by a Polish-US physician Albert Sabin. The vaccine contains weakened polio virus that builds immunity without harming the body. As one of the most necessary medications required in a basic health system, it has been added to WHO’s list of essential medicines.

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          Oncogenes are genes with the potential of causing cancer. Human oncogenes were first discovered by multiple US research teams in 1981. One research team consisted of Prof. Robert Weinberg at the Centre for Cancer Research which is part of the Massachusetts Institute of Technology. Another one was that of Dr. Geoffrey Cooper at the Sydney Farber Cancer Institute, in Boston.

          Oncogenes do not generate cancer by themselves, but do so under the influence of carcinogens, or ionising radiations. Research has isolated cancer genes associated with cancer of different parts like colon, bladder, and kidneys.

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                                                                                                    The link between AIDS and HIV was established in 1983. Human Immunodeficiency Virus (HIV), identified in the 1980s is a group of viruses called retroviruses. Available evidence shows that it affected humans sometime in the late 19th or early 20th century during hunting and butchering of primates. A particular type of chimpanzees in West Africa has been established by scientists as the source of HIV infection in humans.

                The earliest known case of HIV-1 infection of a human was found in 1959 from the blood sample of a man from Kinshasa, Democratic Republic of the Congo.

                Identifying and diagnosing HIV is the first step in availing proper treatment. Implementing identification strategies are crucial to improve quality of life of infected individuals and reduce infant and child mortality due to HIV, particularly in sub-Saharan African nations and all around the world.

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          Dolly is the first mammal to be cloned from an adult cell and this made her the world’s most famous clone. A clone has the same DNA sequence as its parent and therefore, it is genetically identical. Researchers claimed that they had used a mammary gland cell for cloning Dolly.

          In the previous attempts at cloning of animals such as frogs, mice, and cows, DNA from embryos had been used.

          Dolly was cloned at the Roslin Institute in Scotland and lived there until her death in 2003 at the age of six.

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             The human genome is a human being’s complete set of genes contained within a sequence of chemical units (adenine, cytosine, guanine or thymine) unique to humans. At present, no human genome has been sequenced completely.

              A draft of the genome sequencing was announced by two rivals- the public Human Genome Project (HGP) led by Francis Collins, and the private Celera Genomics, led by Craig Venter- on 26 June 2000. Neither of these genome sequencing projects was completed. HGP has progressed lesser than the other but permits the public to see their result free of cost whereas, Celera charges people for access. As of February 2004, relatively more information was published by both organizations.

                 Though the work is not complete, researchers have sequenced over a million human genomes by late 2018.

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          The quest to find indivisible particles of matter started as early as 450 BC with the Greek philosopher Democritus. He wondered what would happen if one kept on cutting an apple into smaller pieces. He named those final pieces which could not be cut anymore ‘atomos’. The modern name atom comes from this.

          British Chemist John Dalton revived the ideas of Democritus in the1800s. He developed Dalton’s atomic theory from his research. It states:

a) All substances are made of atoms.

b) Atoms are the smallest particles of matter which cannot be divided further.

c) Atoms can neither be created nor be destroyed.

d) All the atoms of element are alike and have the same mass. Atoms of different elements have different masses.

e) Atoms join together to form compounds and a given compound always consists of the same kinds of atoms in the same ratio.

          Dalton’s theory was accepted worldwide. However, Dalton’s idea that atoms are the smallest particle was disproved with the discovery of protons, neutrons and electrons.