Genomes are like books of life. But until recently, their covers were locked. Finally we can now open the books and page through them. But we only have a modest understanding of what we’re actually seeing. We are still not sure how much our genome encodes information that is important to our survival, and how much is just garbled padding.
Today is a good day to dip into the debate over what the genome is made of, thanks to the publication of an interesting commentary from Alex Palazzo and Ryan Gregory in PLOS Genetics. It’s called “The Case for Junk DNA.”
The human genome, we now know, contains about 20,000 protein-coding genes. That may sound like a lot of genetic material. But it only makes up about 2 percent of the genome. Some plants are even more extreme. While we have about 3.2 billion bases in our genomes, onions have 16 billion, mostly consisting of repeating sequences and virus-like DNA.
The rest of the genome became a mysterious wilderness for geneticists. They would go on expeditions to map the non-coding regions and try to figure out what they were made of.
Read the full, original story: The Case for Junk DNA
