Complex sentence: As a potential vector for gene therapy, gammaretrovirus has some advantages over HIV as a lentiviral vector, specifically the gammaretroviral packaging system does not require the incorporation of any sequences overlapping with coding sequences of gag, pol or accessory gene.
Split into simpler sentences: As a potential vector for gene therapy, gammaretrovirus has some advantages over HIV as a lentiviral vector. Specifically the gammaretroviral packaging system does not require the incorporation of any sequences overlapping with coding sequences of gag, pol or accessory gene.