Answer:
The discovery of the chemical make up of the DNA
Step-by-step explanation:
The DNA structure which consists of Phosphate, Sugar(Deoxyribose) and four protein(Adenine, Cytosine, Guanine, Thymine) was discovered in 1953 by James Watson, Francis Crick and aided by the work of biophysicists Rosalind Franklin and Maurice Wilkin. However DNA is made up of about 3 billion bases in different orders and sequence and the medical process of trying to get the sequence is called DNA sequencing.Each individual or organism has a distinct DNA sequence and certain groups of origanisms or individuals have distinct but similar sequences. This helps to identify and store vital information for medical use and for future reference. Drugs designed for organisms which has similar DNA sequence should be able to work on effectively on both of them.