During Gene Therapy, Bone Marrow Stem Cells Are Removed from the Individual

Multiple Choice

During gene therapy, bone marrow stem cells are removed from the individual. What must happen to those cells before they are injected back into the individual?

A) Viruses act as vectors to carry the normal gene into the genome of the stem cells.
B) The DNA of the stem cells is removed completely and replaced with a new genome that carries the normal gene.
C) The cells are treated with high doses of radiation to destroy any faulty genes. Then, viruses act as vectors to replace those faulty genes with normal ones.
D) The mRNA of the stem cells is completely removed and used to create new normal genes that are then injected into the nucleus of the stem cells.