Craig Venter, the leading cataloger of the human genome, notes that only 3 percent of our genome consists of protein-producing genes, and the rest is “regulatory regions, DNA fossils, the rusting hulks of old genes, repetitious sequences, parasitic DNA, viruses, and mysterious stretches of who-knows-what.” (Venter is careful never to use the term junk DNA.) One truly selfish gene has made a million copies of itself, taking up 10 percent of our genome; it seems to have no function other than self-replication. Genetically speaking, humans are a fast-moving mess. So is everything else.
I know I disagree slightly with some of the numbers and characterizations, but I’ve never quite thought of our genome’s contents in terms of an email inbox gone wild. I have to think about that. It’s an interesting thought … although it would have to be an inbox where the letter from your grandmother depended on the Nigerian Bank Scam and the Boner Pillz For Cheap email in order to even be legible. I hope that isn’t what my inbox will become.
Lots of good thinking about the genome today. Always feel free to ask me a question if there’s something you don’t understand about this, or anything I discuss. I can’t guarantee clarity, but I always try :)
Really, though, most genomes are like an unfiltered inbox, where three or four meaningful messages are surrounded by hundreds of scams and boner pill ads. Our genes are continually stumbling forward, not waltzing.