Great article from h+ magazine from about a week ago: "Rethinking the Promise of Genomics". This is by Terry Grossman, co-author (with Ray Kurzweil) of Fantastic Voyage:
I used to be a big believer in the enormous potential of genomics, and each of my two previous books, Fantastic Voyage and TRANSCEND: Nine Steps to Living Well Forever, had chapters devoted to this topic. The relevant chapter in the earlier book, Fantastic Voyage, published in 2004, was titled "The Promise of Genomics." My co-author in these books, Ray Kurzweil, is widely regarded as one of the world's foremost inventors and futurists, and he has made predictions for what is likely to occur in the future in the field of genomics . Yet, these days I find that I am feeling far less confident at least for the near term about the near term prospects for this "promise."
Here's a key quote by Grossman:
Currently I have moved much closer to the idea of "genetic irrelevance," the idea that in the overwhelming majority of cases, our genes are of much less importance in determining our fate and that the environment in which we live and the lifestyle choices we make are of far greater importance.
Please note that I said this is true in the "overwhelming majority of cases," but it is not true all the time. About one in 20 people is born with an abnormal gene that will create a major problem that can affect life and be quite relevant, either from birth or at some point further down the line. Examples include cystic fibrosis, a genetic disease that can manifest from birth for which we have been doing routine screening for decades and the BRCA-1 and BRCA-2 genes, which dramatically increase a woman's risk of breast and ovarian cancer later in life. But for nearly 95 percent of us, we come off of the assembly line of birth virtually perfect.
Illuminating stuff. Go exercise! It's important that the advocates of science and technology make it clear to the public that we are willing to be pessimistic about a technology's dividends when it looks rational to do so. Grossman's article reminds me of an excellent 2001 article by John Smart, "Performance Limitations on Natural and Engineered Biological Systems":
The more complex any life form becomes, the more it becomes a legacy/path dependent system, with many antagonistic pleiotropies (negative effects in other places and functions in the organism) whenever any further change is contemplated. It seems that evolutionary development, just like differentiation from a zygote or stem cell to a mature tissue, becomes increasingly terminally differentiated the more complex and specialized the organism. One extreme case of this kind of terminal differentiation, at the cellular level, is nerve cells in the human brain, which are so specialized, and the connections they support so complex, that they cannot even replace themselves, in general. Could they eventually learn to do so without disrupting the connectionist complexity that they create in the brain, after their development has stopped? Perhaps not. The more complex the system becomes, the less flexible it is. It gets progressively harder to make small changes in the genes that would improve system, and given how finely tuned so many system elements are, large changes are out of the question.
Because the reasons outlined by Grossman and Smart, I am more in the school that cybernetics (implants, brain-computer interfaces, wearable computing, etc.) will provide the most significant performance upgrades to humans in the nearer term (20-30 years). At first bio-transhumanism will be more of a side phenomenon than the central thrust of the transition. There will be much more effective and reliable means to make humans stronger and faster before we can make ourselves live longer and deeply exploit our own genetics.