April 25 - DNA Day

You probably know that you have trillions of sets of instructions that tell how to build...well, you! Each and every one of your cells has a nucleus packed with DNA, tightly coiled molecules that encode all your genetic information—from how tall you are (or will be when full grown) to eye color to ear lobe shape.

It took generations—and a scientist (who was also a monk) named Gregor Mendel—to come up with the idea of genes.

It took centuries of scientific inquiry and thought—and two scientists named James Watson and Francis Crick—to discover the double-helix structure of DNA. A helix is a curve that sort of spirals or coils around and around. In the DNA molecule, there are two of these curves spiraling around a common axis—and the two curves are joined together with “bases,” which are like rungs in a ladder.

It took about 13 years to sequence the human genome—that is, to map out the 20 to 25 thousand genes, including roughly what they “do,” of a particular human.

And Now...

In the decade since we finished the Human Genome Project—where are we at with DNA?

Humans have sequenced the DNA of many animals, plants, and microbes such as bacteria. We have even sequenced DNA of extinct species such as the mastodon and the wooly mammoth!

We now understand more clearly how various organisms evolved, and which creatures are most closely related. DNA studies have provided tons of evolutionary evidence that agree with other lines of evidence such as fossils and geographical distribution of animals and plants.

We are learning to do genetic engineering. Perhaps someday we can correct birth defects before birth or shut down cancer before it starts!

We can use DNA evidence to help solve crimes—and even to release wrongly imprisoned people who were not able to take advantage of such evidence when they were tried for crimes years ago!

Advances in DNA sequencing have led to huge advances in computer science—and those advances show up in our lives as better search engines like Google and ever more engaging games. We are also now able store vast amounts of information.

We are learning to use DNA nanotechnology to create specific structures including molecular machines and DNA computers. Stay tuned for further advances in this area!

DNA has helped people make advances in history, archeology, paleontology, and genealogy.