Did you know … an instructor lives inside you! … the DNA.

Deoxyribonucleic acid (DNA) is a molecule present in everyone. It contains the genetic information that makes each of us unique or different. DNA is made up of 2 chains of repeating units of phosphate and ribose with their attached nitrogen base. The two chains are wrapped around each other in a spiral called a double helix.

Every cell in a person’s body has the same DNA. Most DNA is located in the cell nucleus (nuclear DNA or nDNA).  Small amounts of DNA are also in the mitochondria (mitochondrial DNA or mtDNA).

 The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). Human DNA consists of about 3 billion copies of the 4 bases.  More than 99 percent of these bases are the same in all people. It is the less than 1% difference that makes each of us unique!

An 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 important when cells reproduce because the new cell needs to have an exact copy of the DNA present in the old cell.

DNA contains instructions written in a genetic code that instructs cells how to carry out their functions. So, you could say the DNA is the body’s genetic instructor. This can be compared to a computer program. For example, a video game program has codes that has instructs how a video game looks and how the characters move.