There are several types of mutations. If one base is lost, this creates a deletion mutation. Cancer is frequently related to mutations. It is possible to modify the information of the DNA in very controlled ways. This is done naturally by viruses.
Genetic engineer utilize the same mechanisms to produce designer genes.
Once in the area of the cytoplasm, the m-RNA becomes associated with ribosomes, and the process of protein formation in the cytoplasm begins. Transcription Gene transcription, the process of producing mRNA, startes in a promoter region. The promoter base sequence serves as a binding site for RNA polymerase and transcription factors. The Primary RNA transcript actually contains more codons, information than necessary, introns and extrons. The excess information is excized to create the actual mRNA that will be utilized to create proteins.