This might particularly interest you:
http://www.lettersofnote.com/2012/08/why-explore-space.htmlThe gist of it is, in 1970 someone asked a director of NASA why billions of dollars were being spent on exploring space when millions of children were still dying on Earth. The response in part explained that NASA's R&D was paving the way for satellites with better weather forecasting, better communications, and better equipment that was making its way into people's everyday lives. While a bit morbid to say, the advancements made by NASA have arguably saved many more lives in the long run.
It's hard to see the point in investing in experimental technology whose payoff is unknown, especially when we have definite problems with feasible solutions. That doesn't mean we shouldn't try. The possible payoffs - cancer cures, age prolongation, enhanced food production, disease and sickness prevention - that can come from investing in gene therapies are just too great to ignore.
As a side-thought, the technological singularity is thought of as the point at which we create an AI smarter than us, triggering a run-away effect of self-improvement. What if we end up doing it to our own race first through intelligence-improving gene modification? Can you imagine the implications of applying that intelligence to solving the rest of our problems?