H+: SENS describes a whole battery of medical treatments that could theoretically defeat the aging process. These treatments range from relatively simple ones like injecting people with enzymes that can break down tough wastes inside of cells, to highly advanced ones like genetically altering trillions of somatic cells in full grown adults. Considering the differential technical challenges, what SENS therapies will most likely become available first, and which will be developed last?
AdG: Some of them are already pretty close: probably the closest is in fact not the enzyme therapy you mention, but the use of vaccines to eliminate extracellular aggregates (especially amyloid). But when we consider the others, actually I wouldn’t like to make the call, because the hardest ones are the ones that the SENS Foundation and I are prioritizing in terms of the early research. In other words, we’re hoping that they will start to catch up with the easier ones. I suspect that the challenge of genetically modifying a high proportion of cells by somatic gene therapy will have been largely solved before we complete the development of all the genes that we want to introduce.
H+: How long will it be until the various SENS treatments are available?
AdG: I think there’s a 50% chance of getting the first-generation SENS therapies working within 25-30 years. But that’s only an estimate, and it’s a highly speculative one: I think there’s at least a 10% chance that we will hit so many unforeseen problems that we won’t get there for 100 years. This is not something special about SENS, though: any technology that’s two or more years away could easily be 100 years away.
H+: In Chapter 14 of Ending Aging you remark:
“We will almost certainly take centuries to reach the level of control over aging that we have over the aging of vintage cars—totally comprehensive, indefinite maintenance of full function—but because longevity escape velocity is not very fast, we will probably achieve something functionally equivalent within only a few decades from now…”
Should this be taken to mean that you don’t believe medical science is improving at an exponential rate?
AdG: No – it’s just because the defeat of aging gets harder and harder as we push lifespans out further.