Your guide to health and prenatal genetics
Mother hold baby

Assess your personalised prenatal risks, choose screening tests, and find nearby maternity clinics

What is DNA?

What is DNA?

“DNA neither cares nor knows. DNA just is. And we dance to its music”

- Richard Dawkins

“DNA provides the music. Our cells and the environment provide the orchestra”

- J. Craig Venter


DNA (or “deoxyribonucleic acid”) is a chemical molecule that contains our unique genetic code. This is like a recipe book which holds the instructions necessary to build and maintain our bodies. DNA is contained in chromosomes, which are found in the nucleus of most cells. 

The genetic code in DNA is made up of four letters (“bases”): adenine (A), cytosine (C), guanine (G) and thymine (T). These four letters are combined into three-letter words. The words make up “genes,” which are like sentences. Genes provide the instructions to make proteins and other molecules which keep cells in your body doing their jobs. Literally, DNA is a book of life.

Most DNA molecules consist of two strands coiled around each other to form a double helix. The letters (bases) are linked together to make a strand of DNA: A (adenine) is always paired with T (thymine); C (cytosine) is always paired with G (guanine).