GMO's or genetically modified organisms have been a controversial subject over the past few years. Some people believe they are more harmful than helpful, but I think that the advantages that GMO's bring outweigh the disadvantages they may have.
http://www.csa.com/discoveryguides/gmfood/overview.php is my print source.
I learned about both the advantages and disadvantages of gmo's. I found that most of the disadvantages were hypothetical. They were a lot of this could happen or it might affect this. An example is that this could form a new allergen for humans. The advantages were more concrete and real. They were things like higher crop yield, stronger plants, and less pesticides and herbacides used all of which are beneficial.