It's being used to acheive gene transplants in the womb. It's not yet done in humans, but it's quite interesting: http://news.bbc.co.uk/1/hi/health/3581727.stm
This is really really interesting. Using HIV to infect target cells for gene therapy opens up so many options. Other retroviruses can only infect dividing cells (where there is no nuclear membrane) but the HIV virus can enter the nuclear envelope and deliver it's contents to the genome. It's interesting that they suggested this method for treatment of cystic fibrosis, which has thus far been treated with adenovirus vectors... there are several problems with this treatment that can hopefully be overcome with the use of HIV instead. Manipulating fetuses in the womb (germ line gene therapy) is not legal here (here being north america), for ethical reasons. It will be interesting to see how sucess of this therapy could affect this view.
