From the discovery of DNA to current tools for DNA editing

Abstract

In 1944, the Journal of Experimental Medicine published the groundbreaking discovery that DNA is the molecule holding genetic information (1944. J. Exp. Med.https://doi.org/10.1084/jem.79.2.137). This seminal finding was the genesis of molecular biology and the beginning of an incredible journey to understand, read, and manipulate the genetic code.

Insights from Pascal Maguin and Luciano A. Marraffini.

The Avery–MacLeod–McCarthy experiment. (A) Avery and his team first isolated a pure extract capable of transforming type II S. pneumoniae into virulent type III from heat-killed type III S. pneumoniae. (B) Then, the transforming material was treated with different enzymes to assess its chemical properties. Proteinase and RNase treatment did not abolish the transformation capabilities of the extract. On the contrary, treating the extract with crude enzyme preparations and organ sera capable of degrading a pure sample of DNA rendered the material incapable of converting S. pneumoniae from type II to type III. Thus, the results demonstrated that DNA is the main component of the extract and that it contains the genetic information necessary to convert type II S. pneumoniae to type III.