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Spotted in the title of a recent paper:
Abstract: The sequencing of the human genome heralded the new age of ‘genetic medicine’ and raised the hope of precision medicine facilitating prolonged and healthy lives. Recent studies have dampened this expectation, as the relationships among mutations (termed ‘risk factors’), biological processes, and diseases have emerged to be more complex than initially anticipated. In this review, we elaborate upon the nature of the relationship between genotype and phenotype, between chance-laden molecular complexity and the evolution of complex traits, and the relevance of this relationship to precision medicine. Molecular contingency, i.e., chance-driven molecular changes, in conjunction with the blind nature of evolutionary processes, creates genetic redundancy or multiple molecular pathways to the same phenotype; as time goes on, these pathways become more complex, interconnected, and hierarchically integrated. Based on the proposition that gene-gene interactions provide the major source of variation for evolutionary change, we present a theory of molecular complexity and posit that it consists of two parts, necessary and unnecessary complexity, both of which are inseparable and increase over time. We argue that, unlike necessary complexity, comprising all aspects of the organism’s genetic program, unnecessary complexity is evolutionary baggage: the result of molecular constraints, historical circumstances, and the blind nature of evolutionary forces. In the short term, unnecessary complexity can give rise to similar risk factors with different genetic backgrounds; in the long term, genes become functionally interconnected and integrated, directly or indirectly, affecting multiple traits simultaneously. We reason that in addition to personal genomics and precision medicine, unnecessary complexity has consequences in evolutionary biology.
Singh, Rama & Gupta, Bhagwati. (2020). Genes and genomes and unnecessary complexity in precision medicine. npj Genomic Medicine. 5. 21. 10.1038/s41525-020-0128-1.
The paper is open access.
Our physics color commentator Rob Sheldon responds,
With the demise of “junk DNA”, we now have the assertion of “junk function” or “unnecessary complexity”.
They are saying in effect “We weren’t wrong about junk DNA, we just thought it had no function, but now we realize it was junk function, unnecessary complexity. It has to be junk because it was created by chance. And we must defend chance, because if we allow it to be designed, you-know-who will win this debate.”
As I recall, the last time we had a debate on “unnecessary complexity” it was pseudogenes. And before that the inverted retina. And before that it was the clotting cascade. You would think they might learn that lesson by now.
Other tablemates in the Uncommon Descent News virtual coffee room threw in suggestions about similar Darwinian phrases we’ve encountered over the years:
We’re told “irremediable complexity” made an appearance in 2011. Of that, Michael Behe said at the time, “Besides the lack of support from calculations or experiments, the authors discuss no possible obstacles to the scheme. I certainly understand that workers want to accentuate the positive when putting a new model forward, but potential pitfalls should be pointed out, so that other researchers have a clearer idea of the promise of the model before they invest time in researching it.” It amounts, it would seem, to a Darwinian notion, which we could politely call hypothesis.
Then there was “gratuitous complexity” in 2012: “He opens his paper by marveling at the ‘baroque and apparently gratuitous complexity’ we see in biology. In particular, he thinks that natural selection is incapable of producing some of this complexity, such as a process called ‘gene scrambling.’ He describes it this way, using an example from the lifecycle of a group of protozoans.”
Both papers reach for a concept called “constructive neutral evolution” — something no one would have thought of if they did not have a good deal of design to explain away.
Possibly, the most productive aspect of Darwinism in these times is the minting of new terminology to tyr to paper over the plausibility gap.
Note: Rob Sheldon is the author of Genesis: The Long Ascent and The Long Ascent, Volume II.
Hat tip: Pos-darwinista