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.