The macaque restriction factor, TRIMCyp, blocks FIV by attacking and disabling the virus's outer shield as it tries to invade a cell. The researchers know that works well in a culture dish and want to determine how it will work in vivo. This specific transgenesis (genome modification) approach will not be used directly for treating people with HIV or cats with FIV, but it will help medical and veterinary researchers understand how restriction factors can be used to advance gene therapy for AIDS caused by either virus.
The method for inserting genes into the feline genome is highly efficient, so that virtually all offspring have the genes. And the defense proteins are made throughout the cat's body. The cats with the protective genes are thriving and have produced kittens whose cells make the proteins, thus proving that the inserted genes remain active in successive generations.
So far there haven't been negative effects seen in the cats. If time proves that the experiment was safe and without consequences, I have three words: I want one.
Link -via TreeHugger