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In the late 19th century [[Friedrich Miescher]], a Swiss [[biochemist]], discovered an unusual [[acid]] in the [[nuclei]] of cells. The acid was named deoxyribonucleic acid, or DNA. In 1944 the American [[biologist]]s, [[Alfred Hershey]], [[Thomas Gilmore]] and [[Martha Chase]] used experiments with [[bacteria]] and [[bacteriophage]]s to show that DNA passed [[gene]]s from one generation to the next.

In the late 19th century [[Friedrich Miescher]], a Swiss [[biochemist]], discovered an unusual [[acid]] in the [[nuclei]] of cells. The acid was named deoxyribonucleic acid, or DNA. In 1944 the American [[biologist]]s, [[Alfred Hershey]], [[Thomas Gilmore]] and [[Martha Chase]] used experiments with [[bacteria]] and [[bacteriophage]]s to show that DNA passed [[gene]]s from one generation to the next.

In countries like Soviet Union discoveries related to DNA and its functions were initially seen as unacceptable due providing hints that the life has been created. Many researchers have lost they jobs in these atheistic societies for being interested in genes and DNA ([[Lysenkoism]]).  

In countries like Soviet Union discoveries related to DNA and its functions were initially seen as unacceptable due providing hints that the life has been created. Many researchers have lost their jobs in these atheistic societies for being interested in genes and DNA ([[Lysenkoism]]).  

At that time, it was unclear how this simple molecule could hold all the complex information controlling the development of humans, animals and plants. Scientists knew it was made of four chemical bases called [[adenine]] (A), [[thymine]] (T), [[guanine]] (G) and [[cytosine]] (C), plus [[phosphoric acid]] and a [[sugar]]. They also knew that the ratios of A and T as well as G and C were always the same, but they did not know the rules that controlled the arrangement.

At that time, it was unclear how this simple molecule could hold all the complex information controlling the development of humans, animals and plants. Scientists knew it was made of four chemical bases called [[adenine]] (A), [[thymine]] (T), [[guanine]] (G) and [[cytosine]] (C), plus [[phosphoric acid]] and a [[sugar]]. They also knew that the ratios of A and T as well as G and C were always the same, but they did not know the rules that controlled the arrangement.