From sharing DNA with a blood donor, to living off takeaways

We explore some of the curious questions that science can answer

Take another armful: when you give blood, you temporarily give away some of your DNA, too (Getty)

I donate blood. The people getting the blood will get a dose of my DNA. Will they always have it? If not, for how long will they carry it?

They don’t get as much DNA as you might think. This is because only body cells contain DNA, and most of what’s in blood is actually fluid. Of the cells that make up the blood, there are red ones and white ones. Red blood cells don’t have any DNA because they lose it during development. The job of red blood cells is to carry oxygen, and they lose their DNA so they can accommodate more oxygen. White blood cells do contain DNA, but there are not that many white cells in the blood, unless a person is fighting off an infection. The National Blood Transfusion Service usually refuses donations from people who are fighting off infection.

So, having said that people who receive blood transfusions do not receive much DNA, what happens to the DNA that they do receive? Generally, the cells of the blood are replaced fairly quickly. All of the donated cells will have been replaced within several months following the transfusion, which means that all of the donated DNA will have been broken down and the ingredients recycled.