Genes include the information that defines our traits, or features or characteristics that we inherit from our parents, such as eye colour, height, and hair colour and texture. Any disease caused by an aberration in an individual's genetic composition is referred to as a genetic disease. From a discrete mutation in a single nucleotide in the DNA of a single gene to a massive chromosomal abnormality including the addition or deletion of an entire chromosome or set of chromosomes, the genetic abnormality can range from minor to significant.
Gene therapy is a branch of medicine that focuses on genetically altering cells to provide a therapeutic effect or heal disease by repairing or reconstructing defective genetic material. Gene therapy is an experimental strategy for treating or preventing disease by using genes. In the future, instead of requiring medications or surgery, doctors may be able to treat a disorder by introducing a gene into a patient's cells.