Each gene is identified as being related to the expression of a specific trait. The gene for the desired trait is isolated, and transferred to another organism [1] using methods such as injection by needles, or biolistics (using a type of guns to ‘shoot’ the genetic material into the nucleus of the cell) [13]. In other words, genetic engineering is the technique of artificially modifying the genetic make-up of living organisms. It is even possible to exchange genes over natural species barriers [1]. For example, animal genes may be inserted into plants, and vice versa.