Something to consider: it is now technically possible and within the grasp of hundreds of clinics worldwide to run gene therapy. The only reason they aren't yet doing this is that it takes some increment of time to get things lined up; funding, customers, propagation of knowledge, etc. But all the pieces are in place.

Myostatin or follistatin gene therapy is about as proven as these things get. It exists in heavily muscled natural mutants, including humans (look up brute whippets). Antibody myostatin blockade has just completed phase 2 clinical trials, adding muscle mass to 75 year olds. Chinese labs are turning out myostatin-free dogs. The BioViva CEO organized her own follistatin gene therapy earlier this year in an overseas lab. Five years from now it won't take starting a company level of networking to fly somewhere and do this.

But myostatin for muscle mass is just the best risk/benefit/knowledge picture out of hundreds of alterations that could in theory now be run up in humans, many of which are high risk in the sense that they've only been tried a few times in mice and not followed for a long time. For example adding additional lysosomal receptors to mice restores liver function in old mice to be the same as in young mice. Increased GDF-11 sends stem cells back to work and improves health in old mice.

And so on and so forth. The eager early adopter with a hundred thousand dollars to spend ten years from now could spend the time between now and then mining the research literature and organizing collaborators, making connections with labs overseas and setting up for multiple gene therapies down the line, many of which are associated with interventions shown to delay or turn back specific measures of aging in mice.

This isn't SENS, it isn't repair of underlying damage, but it is a step ahead of what is currently possible.