In the case of genetic disease, options often exist for presymptomatic diagnosis—that is, diagnosis of individuals at risk for developing a given disorder, even though at the time of diagnosis they may be clinically healthy. Options may even exist for carrier testing, studies that determine whether an individual is at increased risk of having a child with a given disorder, even though he or she personally may never display symptoms. Accurate predictive information can enable early intervention, which often prevents the clinical onset of symptoms and the irreversible damage that may have already occurred by waiting for symptoms and then ...(100 of 11784 words)