History The discovery of DNA

Deoxyribonucleic Acid or DNA molecules first discovered by a chemistry expert named Friedrich Miescher German nationality in 1869. Miescher investigated the chemical composition of the cell nucleus. He knows that no cell nucleus consisting of carbohydrates, protein and fat, but rather consists of a substance that has a very high phosphorus of conception. Therefore, the substance found in the cell nucleus, the substance that he called nuclein. This name was later changed to nucleic acid, because acid join them together.

Subsequent study conducted by Fisher in 1880. From the results of his research found the substances in the pyrimidine and purine nucleic acids. These findings are further developed by Kossel Albreent that produces findings that two pyrimidine cytosine and thymine and the two purine adenine and guanine in the nucleic acid, so that the discovery he earned the Nobel Prize in 1910.

In the 1920s, with a distinctive purple dye DNA, which was developed by a German chemist, Robert Feulgen, DNA found exclusively located on chromosome. Therefore, DNA is the expected location for the genetic material. In the same year Phoebus Levine of the Rockefeller Institute (Russian-born biochemist) revealed that sugar is deoxyribose DNA (deoxyribonucleic acid hence its name).

Avery Machlead and Mc Arthy (1944) gave a confirmation of the previous findings that DNA has a direct relationship with the offspring. Further research Chargaff in 1955, through the hydrolysis of DNA prove that the variety of creatures apparently many adenine always roughly equal to the amount of thymine (A = T), as well as cytosine and guanine (S = G). In other words, the rule states that the ratio Ghargaff A / T and S / G is always close to one.

Subsequent research by molecular biologist James Dewey Watson and Francis HC Crick in 1953. The results showed that the DNA does not stand alone as a single chain but rather as two chains that spiral into each other, with bases on the chain attached to the base of the chain to another. In other words, DNA is a double helix. The theory of this model confirmed and refined by MAF Wilkins in 1961. Because of these findings the three of them got in 1962 nobel prize in medicine and physiology.

Bibliography

• Suryo, Human Genetics, (Yogyakarta: Gadjah Mada University Press, 1994).
• James D. Watson, et.al., Rekombinon DNA (A Short Lesson), trans. Vishnu Gunaryo, (New York: McGraw, 1988)