What are reasons to get different types of genetic tests?
• Diagnostic testing is to confirm a diagnosis when a person has signs or symptoms of a genetic disease. The genetic test used depends on the disease for which a person is tested. For example, if a patient has physical features that suggest Down syndrome, a chromosomal test is used. To test for Duchenne muscular dystrophy a gene test is done to look for missing sections in the dystrophin gene. • Predictive testing can show which people have a higher chance of getting a disease before symptoms appear. For example, one type of predictive test screens for inherited disposition to certain cancers, such as colon and breast cancer. Someone with an inherited disposition has an increased chance of getting a disease. This does not mean that the person will certainly get the disease. • Presymptomatic testing shows which family members are at risk for a certain genetic condition. This type of testing is done with people who do not have symptoms when the alteration causing disease in the family is
