Although the mapping of (still only a tiny fraction of) human DNA and the DNA of other species may not deliver the magical gene correlations and “solutions” desired by marketers (the ads keep coming, though!!!), it might offer adventures for our species’ … palaeontologists—and not just for our own.
Comparisons between parts of the human genome and those of other organisms (especially microorganisms) have repeatedly surprised researchers. Every so often they discover entire retroviral DNA sequences embedded in the human genome. To date, 8% of our genome has been identified as originating from “endogenous retroviruses” (ERVs), i.e. viruses that failed to wipe out their hosts, as they should have. This happens because retroviruses infect the eggs and sperm of other organisms, so some “defeated” ones (thousands or even millions of years ago) appear to have become incorporated.
From the discoveries so far, most such cases are considered “dead parts” of the human genome, although this is merely a statement of ignorance about what does what. However, cases of assimilation and functional change (of the former retroviral DNA) have been discovered. For example, the enhancement of the immunity of the former “target” and current “host”.
Although these are mostly in the realm of conjecture (more or less well-founded)—as indeed the overwhelming majority of biotechnologies are—the notion that we carry (genetically) the “sins of the world” seems a lot more entertaining than the idea that there’s a gene for … purity!
(By the way: the idea of the DNA “double helix” you grew up with, you’d better start saying goodbye to it… Quadruple, and we’ll see…)