What Markers Are Not

Another tool of biotechnology is the use of DNA markers to help create a new crop variety.  A very common misconception is thinking that DNA markers physically put a transgene exactly where the scientist wants it in a crop's chromosome (Genetic Engineering Step #4). 

At the moment, it is a completely random chance where a gene gun or Agrobacterium will insert a transgene into a plant's chromosome.  There is some work being done with something called Zinc Fingers, which is showing potential for allowing a specific insertion, but for now, it is not being used routinely with plants.

What DNA Markers Are

DNA markers are a set of tools playing a role in one of 3 ways:

1. Providing a tool in plant breeding (known as Marker Assisted Selection)
2. Identifying successful GMO events
3. Distinguishing varieties

Try This Animation

Work through this animation to see more how DNA markers are used in the plant breeding process.   Clicking this image will open a new window which you can make larger by clicking on and dragging the lower right-hand corner. You will not lose your place on this website page to watch the animation. 

eLesson