Whereas old dependency theory was Marxist in presentation, but nationalist in orientation, seeking to combine a theory of class struggle with a nationalist âthird worldistâ ideology, the new dependency theory is institutionalist in its analysis and political orientation.
Griffith concluded that the type II-R had been transformed into the lethal III-S strain by a transforming principle that was somehow part of the dead III-S strain bacteria. Today, we know that the transforming principle Griffith observed was the DNA of the III-s strain bacteria. While the bacteria had been killed, the DNA had survived the heating process and was taken up by the II-R strain bacteria. The III-S strain DNA contains the genes that form the protective polysaccharide capsule.
Until Griffith's experiment, bacteriologists believed that the types were fixed and unchangeable, from one generation to another. In this experiment, bacteria from the III-S strain were killed by heat, and their remains were added to II-R strain bacteria. While neither alone harmed the mice, the combination was able to kill its host.