Age Reduction Breakthrough?
Since it seems like the upshot of all of this is that Katcher is claiming to have discovered a set of signalling molecules which, when injected, rejuvenate tissue and presumably lengthen life, it runs into one of the most fundamental objections that can be leveled at theory of aging (or cure thereof): of the billions of humans that have existed, how is it that <i>none</i> of them have possessed a mutation which (in this case) endogenously produced the signalling molecules which Katcher is proposing as treatment?  In the case of this proposal this sort of objection is particularly strong, since (though the blog post is silent as to what the treatment is) it&#x27;s given that they are fractions from blood, so they&#x27;re substances which the body produces in some quantity anyway, and which are sufficiently non-dose-specific that Katcher, with limited resources, could devise a reasonably effective regimen.<p>Parabiosis is one of the most striking (and just weird) phenomena in aging research, so efforts to understand what&#x27;s going on with it are liable to bear interesting fruit.  I&#x27;m just pointing out that there&#x27;s good reason to doubt  that this particular &quot;breakthrough&quot; is the &quot;cure.&quot;