pposed to DNA) as the genes vector (a plasmid that carries recombinant DNA in order to implant it into a cell and transform it). A retrovirus is made up 5 separate parts. 1.An “envelope” which surrounds the cell, and is derived from the host cell’s plasma membrane. This enables the retrovirus to couple with the host cell.2.Multiple copies of the envelope’s protein, which is located in the envelope’s lipid bilayer.3.A capsid. Which is a protein shell that contains the last two parts of a retrovirus.4.Two molecules of RNA5.The enzyme reverse transcriptase(a DNA polymerase that uses RNA as its template. It is able to make genetic information flow in the opposite direction (RNA -*DNA) (DNA -*RNA)). The retroviruss doctors use to treat SCID, are slightly different. The RNA is a copy of human ADA genes, and the retrovirus doesn’t make the host cell create new viral cells, it creates new ADA genes. Because once the retrovirus connects with the patients target host cells, the reverse transcriptase makes a copy of the ADA gene, and inserts it into the DNA of the cell, thus making the host cell create more ADA. Most procedures use T- cells, or blood stem cells for retrovirus hosts, this is because they travel through, or have immediate access to the bloodstream, and live long, thus reducing the amount of times a year this procedure must be done....
