Not every cell in our bodies actually contain DNA. There is typically a lack of DNA in our mature red blood cells and cornified cells which are found in hair, skin, and our nails. These cells don’t contain a nucleus.
It turns out, our red blood cells are actually trained to destroy their cells nuclei. They do this to maximize the amount of oxygen they’ll be able to deliver through our blood capillaries. So they destroy their nuclei to ensure that we can the most amount of oxygen possible. That’s kind of cool, right?
Cornified cells also lack their nucleus — they start with one to ensure that they develop properly but destroy them so they can maximize their space to carry the protein keratin.
Besides mature cells (red blood cells & cornified cells) all of our others cells contain their nucleus. Our body is capable of some many amazing things!