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DNA has been portrayed on philatelic issues Darwin has appeared on many issues around the world, notably the David Gentleman designed GB set from 1982, and the Poland stamp (SG 1126) from 1959’s Famous Scientists set. Mendel is most memorably depicted on a small, engraved design from Czechoslovakia in 1965, but also appeared on issues from Danzig in 1939 (SG 285), Austria in 1984 (SG 1987), and the Vatican City in 1984 (SG 806-7). Unfortunately, Mendel’s findings were ignored for more than 30 years. Finally, in 1900, the Austrian Dr. Friedrich Tschermak alerted the world to the importance of Mendel’s work. Tschermak was recognised by his home country on a 1971 stamp (SG 1627) for his birth centenary. In 1902, the American, Walter Sutton, proposed that the chromosomes were the site of Mendel’s hereditary factors. In 1910 Albrecht Kossel (1853-1927), a German physician, was celebrated on a 1970, 70 ore issue from Sweden (SG 637) Thomas Hunt Morgan, 1866-1945, received the Medicine Prize in 1933 for ‘the role of the chromosomes in heredity’. By 1944, Oswald T. Avery, McLeod and McCarthy showed that the component that carries genetic information was DNA. In 1952 Alfred Hershey (seen on a 1995 Guyana set alongside Kossel, Crick and Jacques Monod) and Martha Chase confirmed that the DNA molecule formed the basis of inherited characters. Seeking the structure Between 1951 and 1953 there were four young scientists, and a genius, who were actively chasing the DNA molecule. The genius was the distinguished US chemist, Linus Pauling. Pauling has featured on a 1977 issue for Nobel Prize winners from Upper Volta (SG 455), and protein molecular structure features on a Japan 15 yen stamp from 1967 (SG 1095) The technique of X-ray crystallography had been pioneered in 1912 by Sir Lawrence Bragg and his father, William Henry Bragg, and both were celebrated on a 13p GB stamp from 1977. Watson and Crick were using Tonka Toy beads in their attempts to create a model of the DNA molecule. Early in 1953, using the results obtained by Rosalind Franklin and Wilkins, the four young scientists achieved world-wide fame with their discovery of the ‘Double Helix’. The helix appears on stamps of a number of countries. Crick and Watson have been the subject of many philatelic issues from countries such as Guyana, Palau, Zambia, and the Marshall Islands to name a few. Wilkins has appeared on sheets from Palau (in 1999). So far as I can find no country has yet honoured Rosy Franklin on any stamp. Repairing enzyme DNA can be damaged by contact with foreign chemicals. The organism uses an enzyme, DNA polymerase, to repair such damage. The mechanism was discovered by Arthur Kornberg (USA) and Severo Ochoa (Spain). Spain honoured Ochoa with his own 55 peseta stamp in 1994. In 1961 Francois Jacob, Andre Lwoff and Jacques Monod, working at the Pasteur Institute in Paris, developed a model that led them to decipher the genetic codes of the DNA molecule. France marked Monod’s Nobel prize with a 1987 issue (SG 2759). In 1972 Paul Berg took a hybrid DNA from an animal virus and spliced it with DNA from a bacterial virus. Berg featured on a Palau sheet from 1999. The Belgian physician Albert Claude (1899-1983) shared the Medicine Award in 1974, and was remembered on a Belgium issue from 1987 (SG 2901). W. Arber (Switzerland), Daniel Nathans (USA) and H.O. Smith (USA) perfected the discovery and application of restriction enzymes. They have featured on a variety of philatelic releases including issues from Sweden (SG 1484), the Maldives, and Palau. DNA fingerprinting & cloning DNA typing or fingerprinting, was introduced in 1984 by the British researcher, Alec Jeffreys, who discovered the DNA probes necessary for accurate DNA fingerprinting. Barbara McClintock was born in Connecticut in 1902. At Cold Spring Harbor, N.Y. she experimented with the colour variations of maize kernels. McClintock concluded that genes changed their position on the chromosome from generation to generation, in a random way. It also explained how evolution gave rise to the multiplicity of species. Cloning has been the aspect of genetic engineering so far that has aroused the most public controversy. This was successfully done as far back as 1970 with frogs and toads. In 1997 the Scottish scientist Dr. Ian Wilmut, successfully cloned a healthy lamb ‘DOLLY’ – from a female sheep, although the creature died in early 2003. Wilmut featured on a Nevis stamp in 2000 and Dolly got her own miniature sheet from Palau in 1999. |
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