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If we can reconstruct a dinosaur, why not humans?
The idea of reconstructing ancient species such as dinosaur become popular after Michael Crichton published his
novel JURASSIC PARK, in which dinosaurs were reconstructed from DNA cloned from dinosaur cells found in blood-sucking insects
preserved in amber. The exploitation of the scientific basis for studying life preserved in amber starts with another book
THE QUEST FOR LIFE IN AMBER (1994) by George and Roberta Poinar. IN August of 2002, a scientific team announced their intention
to transition from fiction to fact with their plan to clone a prehistoric masterdon using masterdon sperm frozen in the antarctic
and a living elephant.
The searching for ancient DNA has been published in the most prestigious journals such
as Nature and Science. DNA extracted or amplified from salt-preserved quagga tissue (Higuchi et al., 1984), Egyptian mummy
(Lawlor et al., 1991; Nerlich et al., 1997), a magnolia leaf (Golenberg et al., 1990), weevil in Lebanese amber(Cano et al.,
1993) et al., have been reported. The age of the samples dates back from hundreds to millions of years. These DNA studies
based their methods on the Nobel prize-winning technology called Polymerase Chain Reaction (PCR), an extremely sensitive procedure
in which trace amount of DNA are amplified millions of times, like a genetic photocopier. Contamination of samples has been
extremely difficult to avoid. The most recent attempts to reproduce many earlier DNA discoveries have resulted in negative
findings. However, the oldest independently verified DNA extraction (from mammoth bones, etc.) is at least 100,000 years old.
In addition, there can be no question of excellent preservation of tissue ultrastructure - including ribosomes, endoplasmic
reticulum and mitochondria -- for tens of millions of years (DeSalle et al., 1992).
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