Promising Scientific development for self-produced HRT

I just found this article in The Independent newspaper which may be of interest to readers:
From Minnie to Mickey (and all they did was turn off a gene).

The gist of the article is that a group of scientists have developed a simple genetic-based (a modified virus?) technique which can convert the oestrogen producing cells in an adult female mouse to producing normal male levels of testosterone.

The implication is that in several years time, this treatment (and presumably its inverse too) should be available in humans, saving on constant taking of pills or injections for those wanting to go on HRT.