There’s a video on the evidence for evolution going around, but turns out the artist that made that video has made a number of them, including this one on the scientific understanding of a gene.
via Videos / What Exactly is a Gene? – Stated Clearly.
What’s interesting about this, is that the definition of “gene” has changed over the decades. As I understand it, when the word was originally coined, it meant a discrete unit of inheritance, but now it refers to a cistron, a discrete string of DNA encodings that only make up a small percentage of DNA overall, with the remainder initially receiving the nickname “junk DNA”.
As molecular biologists are learning more about DNA and inheritance, it’s becoming increasingly evident that these coding sequences aren’t the whole story, that vast swaths of what was thought was junk DNA are turning out to be part of the process, which is causing many to declare that genes aren’t the whole story. And they’re not, using the modern definition. But by the classic definition, which would include the sequences and any supporting framework in non-coding DNA, they arguably remain the main story.