Gene transfer as a treatment for hemophilia

I think that the article, Evidence for gene transfer and expression of factor IX in haemophilia B patients treated with an AAV vector, published by the paper nature genetics is very interesting, because it speaks about the sex linked disease, hemophilia and even though in the past thought to be uncurable, there has through science now been found a solution to cure this disease.

Sex linked means that the gene is linked to the x chromosome, so that for males, the possibility of expression of the recessive gene is much larger because they just have one x chromosome and no other one to compensate that one if it is diseased. 

The article suggests that there is a adeno-associated  viral vector (AVV) that can be added to person with hemophilia. This protein would then encode the blood coagulation (clotting) factor IX to correct the hemophilic phenotype. Therefore the person would be cured. Furthermore, there is also proved to be no following immune reaction to it so that there wouldn't be a negative reaction with antibodies.


The following source gives an example of the trial on animals:
http://www.nature.com/ng/journal/v24/n3/abs/ng0300_257.html

In this source we see, how the AVV was successfully inserted into humans:http://www.nejm.org/doi/full/10.1056/NEJMoa1108046