Take a look at yourself. Is there anyone the same as you? No.
You are a person with unique physical, mental, emotional make-up. There has never been anyone as you, and never will be. At the same time, you may look a lot like your big brother, or even like your mum. Probably, you have similar hair colour or eyes, or smile in a very similar way. This complete difference or similarity between your brother or mum and you is determined by something in our body called genes.
So what is a gene?
Genes are instruction manuals in our body. They are molecules in our body that explain the information hidden in our DNA, and supervises our bodies to grow in line with that information.
It is believed that each cell in our body contains over 25,000 genes, all working together. These genes carry specific biological codes or information that determine what we inherit from our parents.
Genes are also a small section of Deoxyribonucleic Acid (DNA), a chemical that has a genetic code for making proteins for living cells. Proteins are the building blocks for living things. Almost everything in our body, bones, blood and muscles are all made up of proteins, and it is the job of the genes to supervise protein production.
Genes are not things we see with our bare eyes. They can only be seen with powerful microscopes, and they are thread-like in nature, found in our chromosomes.
The diagram below shows how a gene is represented.
Altered or mutated genes:
Sometimes our genes do not work well. Sometimes we inherit genes that have some problems. Such genes (also called mutated or altered genes) do not perform their functions well, and cause defects in our organs. Some inherited diseases like cancer and sickle cell have been linked to such mutated or bad genes. There is still a lot of research going on in the study of genes to learn more about them.
Remember we mentioned DNA and Chromosomes along the line? Let us see more about them too.