spermatozoa through ionic interactions. The ability of sperm cells to locate and internalize exogenous DNA was then used to transfer foreign genes into an oocyte during fertilization to create transgenic animals. However, a low efficiency rate hinders this technique due to the low uptake of exogenous DNA by sperm cells compounded with the low fertilization rate of the oocyte. See also Mutagenesis Transfection Transduction Gene Transfer Sperm-mediated gene transfer (SMGT) Horizontal gene transfer References DNA