How Much DNA?

Here's a question for you: How much DNA is in a human cell? How much is in the whole human body? To figure this out, we need to do a little math.

One base pair of DNA is about .34 nm long (.00000000034 m). There are about 6 billion base pairs (6,000,000,000) in the human genome. By multiplying these two numbers, we can figure that there is about 2 meters of DNA in a single human cell. By multiplying this number by the 10 trillion (10,000,000,000,000) cells in the human body, we can figure that there is about 20 trillion (20,000,000,000,000) meters of DNA in the human body.

By dividing this very large number by 1000, we get 20 billion kilometers of DNA. (Remember, this is DNA at it's regular microscopic size. We haven't enlarged it at all.) For the sake of comparison, the distance from the Earth to the sun is 150 million (150,000,000) kilometers. This means that each of us is carrying around enough DNA in our bodies to stretch the the sun and back over 65 times!

Pretty cool, huh?