2. DNA for all organisms is composed of the same parts. What makes your DNA different

from another person's DNA?

Humans are 99% identical and what makes each one of us nunique is like 0.1% of our genome and the human genome is up of three billion base pairs which mean 0.1% is still equal to three million base pairs. In those three million differences lies the changes that gives you the green eyes instead of blue eyes etc.