DNA (deoxyribonucleic acid) is a substance containing genetic information that is found inside the centre (nucleus) of most body cells. DNA determines what features a person inherits from his or her parents, such as blood type, hair colour, eye colour, and other characteristics.

Chromosomes are parts of body cells that carry the DNA. The DNA of each chromosome is divided up into genes. Each person's DNA contains tens of thousands of genes.

Changes (mutations) can occur in the DNA of genes or chromosomes. These changes may be harmless and undetectable. Or the changes may affect certain body processes or functions to cause genetic conditions, such as hemophilia, cystic fibrosis, or Down syndrome.

Current as of: October 13, 2016

Author: Healthwise Staff

Medical Review: Adam Husney, MD - Family Medicine & Kathleen Romito, MD - Family Medicine & Brian O'Brien, MD, FRCPC - Internal Medicine & Martin J. Gabica, MD - Family Medicine & Siobhan M. Dolan, MD, MPH - Reproductive Genetics