How Do Genes Work? A Simple Look at Nature’s Instructions

 Genes are tiny sections of DNA that act like instruction manuals for the body. They tell our cells how to build proteins, which are the building blocks of life. These proteins do almost everything in our bodies—from giving us our eye color to helping us digest food or fight off infections.

To understand how genes work, let’s start with DNA. DNA stands for deoxyribonucleic acid. It’s a long, spiral-shaped molecule that carries genetic information. Each DNA strand is made up of four basic building blocks—A, T, C, and G. These letters stand for chemicals called bases: adenine, thymine, cytosine, and guanine. The sequence, or order, of these letters makes up the instructions your body reads.

A gene is simply a segment of DNA with a specific set of instructions. These instructions are usually for making a particular protein. For example, there is a gene that contains the code for making insulin, a hormone that controls blood sugar. If this gene is working properly, your body produces the right amount of insulin. If something goes wrong with the gene, it may lead to health problems like diabetes.

Each cell in your body—except red blood cells—contains all your genes. That’s around 20,000 to 25,000 genes in total! But not every gene is active in every cell. For instance, the genes that control how your eye works are active in your eye cells, not in your skin cells. This process is called gene expression. Your body “reads” only the genes it needs in a particular cell type.

Sometimes, genes don’t work the way they should. This can happen due to mutations—small changes in the DNA sequence. Some mutations are harmless, while others can cause diseases. These can be inherited from parents or happen randomly during your life. Scientists study these changes to understand how illnesses develop and how they can be treated or prevented.

Your genes don’t work alone. They interact with each other and with your environment. For example, you might have a gene that increases your risk of heart disease, but a healthy diet and regular exercise might help reduce that risk. This shows that both nature (your genes) and nurture (your lifestyle) play important roles in shaping who you are.

In summary, genes work by giving your body the instructions to make proteins, which carry out most of the functions that keep you alive and healthy. While we can’t change the genes we’re born with, understanding how they function gives us insight into everything from personal health to how life itself operates.