Mutations for Kids: Changes in Genes and What They Do (Grade 8 Science)

Hi, I'm Luna from DoodleBeez. Your genes are instructions written in a code called DNA. Sometimes that code changes. A change in the DNA of a gene is called a mutation. Let's explore what mutations do.

DNA is written with four chemical letters, A, T, C and G. A gene is a section of DNA with instructions for making a protein. Proteins build structures and do jobs in your body.

A mutation can happen when a cell copies its DNA and makes a mistake. Mutations can also be caused by things like ultraviolet light or certain chemicals. A letter may be changed, added or removed.

Because genes code for proteins, a mutation can change a protein's shape. The shape of a protein controls its job. So a changed protein may work differently, or not work at all.

Mutations have three possible effects. Many are neutral and cause no noticeable change. Some are harmful, like those that cause certain diseases. A few are helpful and give an organism an advantage.

Here is a helpful example. Imagine a mutation gives a mouse darker fur on dark soil. Hawks spot it less often, so it survives to have babies. Mutations in egg or sperm cells can be passed to offspring.

Now it's your turn. A mutation changes one DNA letter, but the protein still works exactly the same. Is it harmful, helpful or neutral? Pause and try. It is neutral, because there is no effect.

Great job! Remember, a mutation is a change in DNA. It can change a protein, and its effect can be harmful, helpful or neutral. Practice mutations in the Science Lab at doodlebeez.com. See you next time!