You’re Carrying Billions of Kilometers Worth of DNA Right Now

<p>DNA is one of those scientific concepts that are so influential and fascinating that practically everyone knows about it. Every year on April 25th, we celebrate National DNA Day to commemorate the completion of the Human Genome Project in 2003 and the discovery of the double helix in 1953.</p> <p>The incredible advancements in genetics and genomics have transformed our understanding of life. To mark this occasion, let’s check out some fascinating facts on DNA.</p> <h2>10 facts on DNA</h2> <h3>1) DNA stands for…</h3> <p>Deoxyribonucleic acid (DNA): it's a molecule that holds the “blueprint” an organism needs to develop, function, and reproduce. DNA’s instructions are coded into your genes, which are segments of DNA.</p> <figure><img alt="Gene | Source: National Human Genome Research Institute (NHGRI)" class="img-responsive img-fluid mx-auto d-block" src="https://cdn.storymd.com/optimized/VdKp7ZhwqK/thumbnail.jpg" /> <figcaption>A gene is a region of DNA that encodes function. <em>Source: National Human Genome Research Institute (NHGRI)</em></figcaption> </figure> <h3>2) The human genome is pretty big</h3> <p>If you were to fully stretch out the DNA in just one human cell, it would be around 2 meters long, yet it fits into a microscopic cell nucleus.</p> <p>The human genome is made up of 3.2 billion base pairs (the building blocks of DNA).</p> <h3>3) Almost every cell has some DNA</h3> <p>Nearly every cell in your body has a complete set of DNA, from skin cells to blood cells and muscle cells to the cells in your hair.</p> <figure><img alt="Cell with DNA | Source: NHGRI" class="img-responsive img-fluid mx-auto d-block" src="https://cdn.storymd.com/optimized/PqEpZjf1d2/thumbnail.jpg" /> <figcaption>Cell with DNA. <em>Source: NHGRI</em></figcaption> </figure> <h3>4) DNA is old</h3> <p>DNA as we understand it today has evolved over billions of years, but the oldest DNA samples ever found are from ancient organisms that lived 2.4 million years ago. These DNA fragments were recovered by a Danish team from an ice sheet in northern Greenland and represent more than 135 different species.</p> <h3>5) It’s a bit like Play-Doh</h3> <p>One of the most science fiction-y advancements in modern times is a technology called CRISPR-Cas9, which facilitates gene editing and DNA modification. It’s a hugely exciting area that has the potential to treat genetic disorders, create genetically modified organisms, and possibly cure diseases.</p> <p>Last year saw the world’s first CRISPR therapy become approved to treat sickle cell disease and beta-thalassemia.</p> <figure> <figcaption> <figure><img alt="CRISPR-Cas9 Editing of the Genome | Source: Ernesto del Aguila III, NHGRI" class="img-responsive" src="https://cdn.storymd.com/optimized/YqGBQmF1dl/thumbnail.jpg" /> <figcaption>CRISPR-Cas9 Editing of the Genome. <em>Source: Ernesto del Aguila III, NHGRI</em></figcaption> </figure> </figcaption> </figure> <h3>6) Identical twins have (almost) identical DNA</h3> <p>Unsurprisingly, identical twins start out extremely similar, but their DNA tends not to be exactly 100% identical. Epigenetic and environmental differences through life can further the gap, making for a complex picture of nature and nurture. Over time, their DNA can become slightly different.</p> <h3>7) DNA offers clues on ancestry and health risks</h3> <p>Another reason why DNA is so well-known is the hugely popular ancestry kits like 23andMe and AncestryDNA, which can provide insights into your ancestry and potential risks based on your genetic makeup. For those curious about where their long-gone relatives came from, kits like these can open up conversations you never thought possible.</p> <figure><img alt="Human Origins and Ancestry | Source: National Human Genome Research Institute (NHGRI)" class="img-responsive img-fluid mx-auto d-block" src="https://cdn.storymd.com/optimized/Roev28iadv/thumbnail.jpg" /> <figcaption>Genomics is illuminating human and family origins at a level not previously possible. <em>Source: NHGRI</em></figcaption> </figure> <h3>8) 99.9% of human DNA is identical</h3> <p>Bigots beware: all humans are 99.9% identical in their genetic makeup, and the differences are only apparent in the remaining 0.1%, which is what makes each of us unique. This fractional percentage also holds important clues regarding the causes of diseases.</p> <h3>9) You have a mini-computer inside you </h3> <p>Scientists have figured out that DNA can be used as a storage medium for digital data. It did, after all, evolve to store massive amounts of information at a very high density. According to Mark Bathe, an MIT professor of biological engineering, a coffee mug full of DNA could theoretically store all the world’s data. How crazy is that?</p> <p>Properly harnessed, DNA as a data storage medium would drastically change how we handle information.</p> <h3>10) DNA is made of tough stuff</h3> <p>Despite being incredibly tiny, DNA has a remarkable ability to repair itself when damaged. Repair pathways include base excision repair, nucleotide excision repair, mismatch repair, and double-strand break repair. These processes can fix a wide range of DNA lesions and errors, securing the integrity of the genetic code.</p> <h2>More on DNA and Genetics</h2><ul><li><a href="https://soulivity.storymd.com/journal/zjbxlyzc2w-deoxyribonucleic-acid" target="_blank">Deoxyribonucleic Acid (DNA)</a></li><li><a href="https://soulivity.storymd.com/journal/m9ab49d1gj-human-genome-project" target="_blank">Human Genome Project (HGP)</a></li><li><a href="https://soulivity.storymd.com/journal/j478zb8inj-genomics-101" target="_blank">Genomics 101</a></li></ul>