The human genome (the genetic code in each human cell) has 23 DNA (deoxyribonucleic acid) molecules (called chromosomes) and each DNA contains 500,000- 2.5 million nucleotide pairs. An uncoiled DNA molecule is 1.7-8.5 cm long – the average could be around 5 cm. A human body contains around 37 trillion of such cells and if we uncoil all DNA encased in each cell and place them end to end, it would measure around 200,000,000 km, which is enough for 17 sun-to-Pluto roundtrips. The distance between sun and Pluto and back is 120,000,000,000 km. Interestingly, we share 99 per cent of our DNA with every other human being, which means we are far more similar than otherwise.