Unlock a few secrets of the genetic code with a simple LEGO DNA tower

What can LEGO® bricks teach us about DNA? These colorful bricks can help us understand how sequencing works in the genetic code!

Let's dig into the basics of DNA and then we'll get to how to build your a simple LEGO DNA tower out of the bricks you already have lying around your home.

What is DNA? 

DNA is the material that carries all the information about how a living thing will look and function. It is found in the nucleus of each of our cells and is unique to every individual. Its full name is deoxyribonucleic acid, which can be complicated to say, so we usually refer to it as DNA for short.

DNA is so tiny that it can not be seen unless we use a very powerful microscope. If we could see it we would see that it looks like a twisted ladder, which scientists refer to as the double helix.

The DNA ladder is composed of rungs that are made from two letters of the DNA alphabet. This alphabet consists of only 4 letters — A, T, G, and C. Each letter has a unique puzzle-like shape, which means that A and T fit with each other to form a rung on the ladder and G and C fit with each other to form a rung on the ladder.

As we read the DNA ladder, the letters combine to form 3-letter words called codons. Then, these codons combine to form sentences that we call genes. These genes are the basis for your chromosomes, which give your body a blueprint set of instructions for life.

Every human has 23 pairs of these DNA chromosomes that tell our body what to look like and what to do. We get one set of chromosomes from our mother and one set from our father. They determine whether your eyes will be blue or brown, what color your skin and hair will be, whether you will be a boy or girl and so much more.

How to make DNA tower with LEGO bricks

You will need:

• 2 different colors of LEGO bricks with 6 studs (at least 6 bricks of each color)
• 2 different colors of LEGO bricks with 4 studs (at least 6 bricks of each color)

In this activity, you are going to build a tower that is twelve rows high with the four different colors to see how different combinations you can make. Use the process as you build:

1. Collect the LEGO bricks. You will need at least 2 different colors of bricks different with 4 studs, such as yellow and green, and 2 different colors of bricks with 6 studs, such as red and blue.
2. Assign each color one of the 4 DNA-letters. In other words, if you have red, yellow, green, and blue. You can choose that red and yellow will go together, just like the A and T in DNA, and green and blue will go together, just like the G and C in DNA.
3. Make a tower that has twelve rows. As you build, remember that a certain color can only pair with the other color you have chosen and that each row can only have two bricks. (Note - You should be able to come up with many different combinations, just like DNA.)
4. Now that you have created a DNA ladder, use it to write a gene sentence. Do this by writing down your codons, or 3 letter words, from top to bottom and left to right.  As you work your way through the tower, you will create a unique gene-like sentence.

The sentence for the tower pictured above would be:

RYG BYR BGG BYR BGR YYR BGG BRY

More Genetics Activities

Here is another activity you can use to study DNA:

• DNA extraction activity - Join Uncle Cecil from Sassafras Science as he shares how you can extract DNA from a piece of fruit.

Here is another activity you can use to learn about the Punnett Square:

• Punnett Square - Learn about this fundamental concept in genetics and put that knowledge into practice with a free printable.

I hope that you find the explanation and activities in this post useful as you seek to share about DNA with your students! If you have any questions, please feel free to leave them in the comments below.