How Much DNA Codes for Protein?

The human genome: genes and non-coding DNA. Originally created for DNA Interactive ( http://www.dnai.org ). TRANSCRIPT: Think of how many letters fit on a single page and now imagine a stack of pages three hundred feet tall. That's how much information is stored in the DNA inside every human cell: the entire human genome. If you sort through the three billion letters that make up the human genome, you find some surprising things. Only about 1% of the three billion letters directly codes for proteins. Of the rest, about 25% make up genes and their regulatory elements. The function of the remaining letters is still unclear. Some of it may be redundant information left over from our evolutionary past.