These heel-prick blood specimens are obtained at the time when blood is drawn for thyroid tests and a number of other inherited diseases. These screening programs have achieved their goals. Diagnostic methods are continually being refined, both for the hormonal methods, and for the newer genetic typing discussed below. Since the advent of molecular genetic technology, we can now examine the genes of CAH patients and family members. This type of study has application for prenatal testing, neonatal screening, and genetic counseling, as well as confirming diagnosis in questionable cases.
Molecular diagnosis is available in several specialized laboratories.
As DNA diagnosis becomes more widely accepted, these tests will no doubt become more widely available. Just as there are potential inaccuracies in hormonal testing, there are pitfalls in genetic testing, as now has become clear from published reports concerning CAH, as well as in the diagnosis of other diseases, and in forensic use of DNA testing. Nonetheless, for the most part, these techniques are verifiable and accurate in the proper hands. Genetic testing can resolve ambiguities that arise from hormonal testing, and can help provide accurate information to parents of CAH patients as to their risk of having another affected child during the early weeks of pregnancy. The public should be somewhat wary of wholesale genetic testing, first because of the potential for misinterpretation by inexperienced personnel, and second in light of disconcerting reports of such data being used to restrict insurance coverage or employment.