From: Evolution: The Fossils Speak, but Hardly with One Voice
5. Far too much attention may be given to genes and DNA. So much current evolution thinking, including questionable fields like evolutionary psychology, depends on the alleged power of the gene. Does anyone remember that fellow who said in the early 90s that a CD of your genome is “you”?
Not even close. From the New Statesman: “According to a growing number of researchers, the standard story of the influence of genes is overblown. So many other factors influence how we turn out as individuals and how we evolve as a species that the fundamentals of biology need a rewrite.” “This is no storm in an academic tearoom,” a group of biologists wrote in the journal Nature recently: “It is a struggle for the very soul of the discipline.”
The gene isn’t even necessarily what we think. Diverse genomes can exist in a single person: Mothers’ cells may remain in their children and children’s cells in their mothers decades after childbirth. So that CD of your genome is both you and your mom?
There are some relatively new genes. There are also “hidden” genes that don’t show in current populations but might later. Some genes are not “junk” but also not strictly necessary either: “In the late 1990s a team of researchers at Stanford University created around 6,000 mutants of brewer’s yeast, each of them lacking a different single gene, and found that many of them thrived just as well as the unmutated yeast did.” No surprise there; successful life forms would feature redundant systems.
Some life forms can edit their genes extensively. Squid can, apparently. A researcher noted, “It was astonishing to find that 60 percent of the squid RNA transcripts were edited.” The iconic fruit fly is thought to edit only 3 percent of its makeup.
Some species can have more than one genetic origin. Polyploidy, which means that the species has two complete sets of chromosomes, has been identified in a mimulus plant in Scotland. We learn that polyploids “are common among plants, as well as among certain groups of fish and amphibians. For instance, some salamanders, frogs, and leeches are polyploids.” and “Mimulus peregrinus is an example of how some branches can come back together again and spawn new species that are in part the combination of their ancestors.”
Basic claims about inheritance principles are also coming under fire. Researchers recently found that Mendel’s “law of segregation” (an equal probability of inheriting each of two copies of each gene from both parents)doesn’t always hold. We now learn, “For years, scientists had evidence that this law was being broken in mammals, but they didn’t know how.” Apparently, female mice pass on one copy of the R2d2 gene more frequently than the other copy. This finding, if it holds, matters because the probability of heritable illness is calculated by doctors assuming Mendel’s Law. But maybe it’s not a law.
Not surprisingly, some respected researchers now <href=”#ref-list-1″>question the amount of attention given to the gene as such. A recent Royal Society paper denotes genes as “merely a means of specifying polypeptides.” Whether the researchers are right or wrong, they add to a growing chorus against the vision of evolution that started with Darwin and was revived by Mendelian genetics, as natural selection acting on random mutation of genes to create the world of life we see around us.More.