Molecular Genetics Grows Up

As the field of molecular genetics grew, the DNA molecule became the focus of many research efforts. Francis Crick and George Gamov developed the sequence hypothesis to explain how DNA makes protein. They stated that the DNA sequence specifies the amino acid sequence of a protein and postulated the central dogma of molecular genetics the flow of genetic information is a one-way road, it always takes the direction from DNA to RNA to protein [16]. In the same year, 1957, Mathew Meselson and Frank Stahl demonstrated the replication mechanism of DNA [17]. In 1958, DNA polymerase became the first enzyme used to make DNA in a test tube. 

The work of Marshal Nirenberg and Heinrich Matthaei between 1961 and 1966 resulted in the cracking of the genetic code [18]. They demonstrated that a codon consisting of three nucleotide bases determines each of the 20 amino acids. 

The first transgenic animals were produced in 1981 at Ohio University [24] and the technical developments towards powerful and efficient automated DNA 

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