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Happy DNA Day!

Today, April 25, is National DNA Day. This is an obscure holiday, ranking somewhere above International Violin Day but probably below the recent pi day, or even the upcoming May the 4th be with you.

It celebrates something important, though. National DNA Day commemorates the successful completion of the Human Genome Project in 2003 and the discovery of DNA’s double helix by James Watson and Francis Crick in 1953.

DNA stands for DeoxyriboNucleic Acid. The “nucleic” part means it is found in the nucleus of all cells. There are many different ways to visualize DNA. These are some of the most common:

Francis Crick's DNA model, Rosalind Franklin's X-ray crystallography, a schematic double helix, a bacterial chromosome, some DNA isolated in the lab
Different views of DNA

The upper left shows Watson and Crick’s original wire model of the DNA double helix. On the lower left, the abstract X is one of Rosalind Franklin’s X-ray crystallograms that were used to help determine the structure. The upper right, looking like a beaded necklace, is a bacterial chromosome viewed under an electron microscope. And the lower right, with what looks like some cloudy snot in a tube, shows some DNA extracted from strawberries with common kitchen materials.

The center picture shows the DNA double helical model that has entered popular culture. A DNA molecule is composed of two complementary strands that wind around each other in a helical shape, a “twisted ladder.”  The rungs of the ladder, in primary colors, are the base pairs, which spell out the genetic code.

This song from “They Might be Giants” explains in 2 and a half catchy minutes how the DNA instructions are translated into making different cell types.

Every year the American Society for Human Genetics sponsors an essay contest for high school students and announces the winners on DNA day. This year’s question was about genetic testing.


Do you think medical professionals should be required for all genetic testing, or should consumers have direct access to predictive genetic testing? 

Check out some of the winning essays here on their website. Congratulations to all who entered!