State of the Art

Olivia Judson is back and posting on her NY Times blog. This week she is puzzling over what genome to decode. Here's an interesting bit from the article:

At the moment, our ability to interpret whole genomes is patchy: it’s like trying to read a foreign language with an incomplete dictionary and grammar. We don’t yet know what most genes do, or how they interact with each other.

Moreover, a lot of the DNA in a genome does not encode genes, it does . . . something else. What that something else is remains, by and large, to be discovered. Some of it might do nothing at all. (One of the big surprises of the human genome project was how few genes we have. Obviously — or so everyone thought — an animal as magnificent and complex as ourselves must have a lot of genes. Most of the early estimates came in around 100,000 genes; the real number is more like 24,000. This is about the same as a sea urchin — around 23,000 genes — and rather fewer than rice, which boasts around 50,000. More than 95 percent of the human genome does not contain genes.)

I remember how introns and exons were first talked about and the introns were called "junk DNA" and viewed as worthless. Judson indicates that not much function has been found for the introns, but I would really be surprised if they were "superfluous". The pattern of science that I see is that the wall between known and unknown keeps moving into the unknown territory and stuff that was deemed unimportant or useless ends up having some importance and use. She at least indicates that it is reasonable to wait to discover functions for the introns.