Decoding human DNA can help us understand how cutting edge genetic breakthroughs are helping people predict, prevent and prevail over their future health risks much before they cause irreversible damage. To begin with let us understand the basics of DNA.
DNA stands for Deoxyribo Nucleic Acid. DNA is the hereditary material in humans and almost all other organisms that is passed from one generation to the other. DNA contains the instructions an organism needs to develop, live and reproduce. These instructions are found inside every cell and are passed down from parents to their children. The entire human genome contains about 3 billion (600 Crore) base pairs and about 25,000 genes. Interestingly, 99.9% percent of these bases are same in all people. However, the balance 0.1% is unique which makes all the difference.
DNA is made up of molecules called nucleotides. The information in DNA is stored as a code made up of four chemical bases i.e. A (Adenine), T (Thymine), C (Cytosine) and G (Guanine). These DNA bases pair up with each other - A with T and C with G, to form units called base pairs. Each base is also attached to a sugar molecule and a phosphate molecule. Together, a base, sugar, and phosphate are called a nucleotide.
Nucleotides are arranged in two long strands that form a spiral called a double helix. The structure of the double helix is somewhat like a ladder with the base pairs forming the ladder’s rungs and the sugar and phosphate molecules forming the vertical sidepieces of the ladder. The order or the sequence of these bases determines the information available for building and maintaining an organism, like alphabets appear in a certain order (spelling) to form words and sentences. This genetic code or the order of nitrogen bases in DNA sequences form genes, which is the language of the cell, which tells the cells how to make proteins. Another type of nucleic acid, RiboNucleic Acid (RNA) translates genetic information from DNA into proteins. Every cell in a person’s body has exactly the same DNA. Now, the important property of DNA is that it can replicate or make copies of itself. Each strand of DNA in the double helix can serve as a pattern for duplicating the sequence of bases. This is critical when cells divide because each new cell needs to have an exact copy of the DNA present in the old cell.
However, sometimes, when cells in the body replicate to make new cells, mistakes are made. Hence a gene that was supposed to code for a specific word now reads it differently by changing just one letter or just one base. Now, the gene has a totally new meaning and function. These variations are called Single Nucleotide Polymorphisms (or SNPs). These changes or mutations in bases that code for a protein in the body can be very profound. Just imagine hypothetically that if CAT coded for a cat and then a mutation in your sequence changed the C to an R you would get RAT which would code for a completely different animal. That’s how impactful these changes can be.
These small variations in DNA are expressed in many ways. They can influence how we metabolize food and what types of exercise are best suited for our body. By identifying our own unique gene variations, we can customize lifestyle approaches and nutritional supplementation to maximize our genetic potential promoting optimal health like never before. Essentially, cracking your genetic code is like rediscovering yourself.