in order to provide better prognosis as well as medical management and/or treatment options. Testing can reveal conditions can be mild or asymptomatic with early treatment, as opposed to debilitating without treatment (such as phenylketonuria). Genetic tests are available for a number of genetic conditions, including but not limited to: Down syndrome, sickle cell disease, Tay–Sachs disease, muscular dystrophy. Establishing a genetic diagnosis can provide information to other at-risk individuals in the family. Any reproductive risks (e.g. a chance to have a child with the same diagnosis) can also be explored after a diagnosis. Many disorders cannot occur unless both the mother and father pass on their genes, such as cystic fibrosis; this is known as autosomal recessive inheritance. Other autosomal dominant diseases can be inherited from one parent, such as Huntington disease and DiGeorge syndrome. Yet other genetic disorders are caused by an error or mutation occurring during the cell division process (e.g. aneuploidy) and are not hereditary. Screening tests are often used prior to diagnostic testing, designed to separate people according to a fixed characteristic or property, with the intention of detecting early evidence of disease. For example, if a screening test during a pregnancy (such as maternal blood screening or ultrasound) reveals a risk of a health issue or genetic condition, patients are encouraged to receive genetic counseling to learn additional information regarding the suspected condition. A discussion of the management, therapy and treatments available for the conditions may take place; the next step may differ depending on the severity of the condition and range from during pregnancy to after delivery. Patients may decline additional screening and testing, elect to proceed to diagnostic testing, or pursue further screening tests to refine the risk during the pregnancy. Presymptomatic or predictive testing occurs when an individual knows of a specific diagnosis (typically adult onset) in their family and has other affected relatives, but they themselves do not manifest any clinical findings at the time when they seek testing. The decision about whether or not to proceed with presymptomatic testing should entail a thoughtful approach and consideration of various medical, reproductive, social, insurance, and financial factors, with no "right" or "wrong" answer. Availability of treatment and medical management options for each specific diagnosis, as well as the genetics and inheritance pattern of the particular condition should be reviewed as inherited conditions can have reduced penetrance. Insurance and legal issues should