Via the Gerontology Research Group mailing list, my attention was drawn today to a proposal from biologist João Pedro de Magalhães and others to sequence the genomes of certain exceptionally long-lived mammals.
The proposal focuses on three organisms (in order of priority): the naked mole-rat (Heterocephalus glaber) whose record longevity of 28.3 years makes it the longest-lived rodent, the white-faced capuchin monkey (Cebus capucinus) which can live over 50 years, and the bowhead whale (Balaena mysticetus), the longest-lived mammal with an estimated longevity of over 200 years. If approved, these organisms will be added to the queue of target organisms to be sequenced, the sequencing will be carried out in one of the NHGRI-funded sequencing centers, and the entire genome sequences will be deposited in free public databases.
Aging is not only a major puzzle of biology but it has a profound impact on medicine with age-related diseases like heart diseases, type II diabetes, cancer, and neurodegenerative diseases among the leading causes of death in modern societies. Recent research has revealed several gene systems that can regulate longevity, aging, and multiple age-related diseases in short-lived model organisms. Nonetheless, the longevity effects of these genes are modest when compared to the lengthening of lifespans during evolution. Among mammals alone there is at least a 40-fold variation in maximum longevity. We still do not know why different species of similar body plan, biochemistry, and physiology can age at such different rates, but these differences must be seated in the genome.
In this white paper, we champion the idea that longevity should also be taken into consideration when choosing target organisms for sequencing, and we propose the sequencing of three organisms of unique interest for aging research (in order of priority) ... In particular Heterocephalus and Cebus have a much longer lifespan than expected for their body size.
The scientists backing the proposal are looking for letters of support from other engaged life scientists; give it some thought if you fit that description and are supportive of government-funded work on genome science.
As for myself, I am neither of these things, but the basic idea seems more interesting in many ways than the search for longevity genes in humans. I have mentioned whale longevity in the past; it is one good example of the way in which mammalian biochemistry could be reconfigured to be far more efficient than human biochemistry. Whales have many times as many cells as we do, and thus many times the risk of cancer, were they built the same way as humans - but they still make it through multiple centuries of life. For all that, the naked mole-rats are in many ways even more impressive, living more than eight times longer than similarly-sized peers in the animal kingdom.
A couple of other items of interest from the past on animal longevity:
- Ageless Animals, the Turtle Edition
- Ageless Animals, Absent Immortality, Evolutionary Biology and Aging
I don't see the re-engineering of our biochemistry for longevity as a short-term proposition - it's a fearsomely complex undertaking. This sort of endeavor sounds like something we'll see much more of around the time that the first reseachers are designing entire human genomes with a good idea as to how to make things better. This will likely prove to be decades past the time at which we could have learned how to repair age-related damage in our present biochemistry. First things first, I say, for all that these prospects for the future are exciting ones.