Deleterious alleles are, by definition, not beneficial and should be selected out. However, sometimes deleterious alleles are maintained in a population, despite their harmful effects. Scientists have proposed several explanations for this unintuitive quirk of biology. Overdominance, otherwise known as heterozygote advantage, and mutation-selection balance are two such explanations.
Tag: mutations
Resource Review: Genetic Entropy
We are constantly told that evolution can build the genome over time, through chance mutations favored by natural selection. But what if this claim is false? What if the genome is not improving? What if, instead, it is actually degrading over time? Further, what if the scientific community has known this for decades and refuses to acknowledge it because of the damage it would do to evolution? Welcome to the premise of Dr. John Sanford’s book, Genetic Entropy. In the book, Sanford, a former evolutionist and emeritus professor at Cornell University looks at whether evolution, the “primary axiom” as he terms it, can work, using population genetics.
E. coli and Evolutionary Genetics
The small bacteria Escherichia coli is a well known and commonly used model organism in science. As such, it makes … More