Really? While we all can agree that there's no definition of "gene" that doesn't have exceptions, we can surely agree that some definitions work pretty well. I've argued that defining a gene as, "a DNA sequence that is transcribed to produce a functional product" works well in most cases [What Is a Gene?].
Let's see how James Shapiro handles this problem.1 He says,
The identification of DNA as the key molecule of heredity and Crick's Central Dogma of Molecule Biology [Crick 1970] initially seemed to confirm Beadle and Tatum's "one gene -- one enzyme" hypothesis.I've already explained that Shapiro doesn't understand the Central Dogma of Molecular Biology even though he quotes the Francis Crick papers that explain it correctly [Revisiting the Central Dogma in the 21st Century]. I also made this point in my review of his book: Evolution: A View from the 21st Century.
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