It is hoped that information from the Human Genome Project will allow scientists to develop new ways of treating or diagnosing illnesses, especially genetic disorders and cancer.
A person with cystic fibrosis has inherited two faulty alleles for a certain gene on one of their chromosomes, chromosome 7. It is hoped that it may one day be possible to repair the faulty alleles using gene therapy, perhaps by putting the normal allele into the cells of the lungs. This would greatly improve the lives of people with cystic fibrosis, who often need lung transplants as their illness progresses.
Members of some families are particularly at risk of developing certain types of breast cancer, because they carry faulty alleles. These alleles have been identified, and it is now possible to test people to see if they have an increased risk of developing breast cancer. This allows them to make decisions, if they wish, about whether to have surgery to remove breast tissue before any cancer develops in their breasts.