Explained: What are genes?

This November, researchers from the University of Oxford found that genetic make-up is affecting the response to COVID 19 virus in patients. Our genes play an important role in determining how we look, what diseases we may develop, our immunity level, even our behaviour and mental make-up. We keep saying that genes pass on traits from one generation to the next. Let’s see how that happens.  

What is a gene? 
Genes carry information determining traits that are features or characteristics passed on through generations in a family, what we inherit from parents and grandparents. Each cell in the human body contains genes, in fact, about 25,000 to 35,000 of them. Genes aren't just found in humans, animals have them too.   

What are genes made up of?  
Genes are found on microscopic noodle-like structures called chromosomes, which live inside our cells. We are made up of billions of cells. Chromosomes come in matching pairs, and there are hundreds, sometimes thousands of genes in every chromosome. The chromosomes and genes are made up of deoxyribonucleic acid (DNA). Chromosomes and genes are housed in the nucleus of the cell, which is like the brain of a cell or the CPU of a computer, and tells the cell what to process. In humans, a cell nucleus contains 23 pairs of chromosomes, half of which come from either parent. Not every living thing has 46 chromosomes, for example, a fruit fly has only 4 inside its cells. Our gender is also determined by chromosomes.  

How do genes function? 
Each gene has a specific job. The DNA in a gene directs how proteins are made in the cell. Proteins are the building blocks for our body, in fact, the CORONA virus is also a rapidly multiplying form of protein. Bones, teeth, hair, cartilage, muscles and blood, are all composed of proteins. Those proteins help our bodies grow, work, and stay healthy. We are made up of more than 3 lakh protein combinations!  

Like chromosomes, genes also come in pairs. Since once, again, each parent contributes 1 gene, we get the characteristics form both sides. This also explains why we sometimes inherit not just eye or hair colour, but also diseases like anaemia, hypertension, high or low sugar levels or bone related diseases.