Let's say you're an alien and you want to make sure your species outlives your planet or whatever disaster you currently face, whether it be natural or engineered. You load up a bunch of self-replicating spacecraft to seed any planets they pass that have complex life with a highly infectious retrovirus (or nanovirus if you feel like there should be/want there to be nanotechnology involved) that will insert modified genes into that organism that will cause it and/or its offspring to develop some of your species' prominent traits, ensuring that your genetic information continues to propagate after you're gone.
Could this work? Would this be a realistic and/or feasible way to either colonize the cosmos or ensure the propagation of your doomed species? What complications might there be for infected organisms? Assume they have access to arbitrarily complex bio or nanotechnology (within the laws of physics).