Take a quick glance around the world. What do you see? Millions of cultures? Thousands of languages? Billions of people? Yes, yes and yes.

With all those billions of differences spread across the Earth, it’s hard to imagine that someone living in Mumbai, India, could be similar to someone from Chichicastenango, Guatemala, or Oslo, Norway, or any other place on the map.

Isn’t the world too big for us to be so similar?

Actually, no. Because the above scenario is exactly the case. Humans are more alike than they are unalike. So just what do you have in common with a person who lives on the other side of the world from you?

It all starts with a little something called deoxyribonucleic acid, or DNA for short.

DNA is a molecule that carries the instructions that tell cells how a living thing will look or function. Humans have two copies of their DNA—one from each parent—that create their physical characteristics. This means that DNA helps determine things like our skin pigmentation, height, and even some of our senses like taste and smell! 

The DNA code includes four chemical bases—adenine and thymine (which bond together) and cytosine and guanine (those go together as well). How those bases line up with one another within DNA sequences form genes. These genes—and the differences in their sequencing combinations—are what create each of our unique traits. In other words, the DNA of your genes makes you different from someone else.

But wait, what happened to everyone being so similar?

Here it is: There are billions of options for how a gene sequences its base pairs—around 3 billion options, in fact. But of all those possible genetic coding combinations, more than 99% of those are the same in all people.

That’s right—over 99% of your genetic code is the exact same as that person in Mumbai or Chichicastenango or Oslo or anywhere else in the world!

So while your DNA makes you unique in that it codes for your specific eye color, height, predisposition to certain illnesses and countless other traits, it doesn’t really make you that unique at all. We are, for the most part, more than 99% the same as any other single person in the world. How cool is that?

The Sanford Connection
Your genes determine certain traits, like your eye color or your hair texture. They also affect your risk of certain health conditions that can be passed down from your family. Understanding your genes can help you and your family make medical decisions. At Sanford Imagenetics, doctors and specialists can use genetic testing to help patients understand disease. Learn more about genetic testing on a podcast featuring Cassie Hajek, MD.