Why might a scientist want to know the sequence of a DNA molecule?

Answer 1

DNA sequence data are used for multiple reasons. For example:

1. To determine the genetic code of a gene that contributes to disease (e.g., the Human Genome Project)

2. To determine the relationship of related species (see systematics)

3. To improve crop performance by locating important genes and breeding plants to carry the right copy of those genes (take a look at Pioneer and Monsanto websites)

4. To understand the history of a population (e.g. gene flow, genetic bottlenecks, levels of inbreeding etc).

And the list goes on...

Answer 2

Multiple Reasons, mainly if you have a roadmap you can see where you are going. You can look for disease causing mutations, you can look for people that are immune to diseases and find out why and actually develop a gene therapy. Eventually you can look into cloning, and developing faster, stronger humans that do not feel pain... just kidding you can do a lot of things once you have that map.