Way back when, genes were those things that passed along inherited traits. Then our understanding of the genome increased, and it was learned that genes do not just pass along a trait, they are pleiotropic, passing along several. Votaries of microbes-to-magician evolution figure that there's a whole heap of beneficial mutations being passed along through genes to future generations. Not hardly!
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In the early days of genetics, genes were thought to be solitary entities. Now it's well understood that genes operate in complex networks and that gene mutations can have multiple detrimental effects. A new study reconfirms mutations are a major roadblock for evolution.To finish reading, click on "Gene Pleiotropy Roadblocks Evolution".
Before the advent of modern molecular biology, scientists defined a gene as a single unit of inheritance. If a gene was found to influence multiple externally visible traits, it was said to be pleiotropic — a term ﬁrst used in 1910. During this early period of genetic discovery, pleiotropy was considered to be quite rare because scientists assumed most genes only possessed a single function—a simplistic idea that remained popular throughout most of the 20th century. However, as our understanding of genetics grew through DNA science, it became clear that genes operate in complex interconnected networks. Furthermore, individual genes produce multiple variants of end products with different effects through a variety of intricate mechanisms. Taken together, these discoveries show that pleiotropy is a common feature of nearly every gene.
Once again, more knowledge about the genome reveals more reasons to reject evolution.