The Genetic History
The indications for testing for MSAFP and Down syndrome depend more on epidemiologic information than patient-specific information. The proper management of other genetic diseases begins with a genetic history. Given that a significant number of children will be born with unanticipated genetic diseases, this history should be carefully recorded and the significance of the questions explained to the patient. In a recent case, a couple sued when they gave birth to a child with Tay-Sachs disease. This couple had received genetic counseling, but no mention was made of testing for this disease because neither member of the couple met the traditional profile for persons at high risk for Tay-Sachs. After the birth of the child and the diagnosis of the disease, an exhaustive review of the parents’ genealogy was done. The mother was found to be descended from a small, closed community of French Canadians who were at increased risk for Tay-Sachs.
The judge found that the physicians had asked the appropriate questions and that the plaintiffs had not given the physicians any information that would have indicated that either was at high risk for Tay-Sachs disease. The judge rejected the plaintiff’s argument that they should have been offered testing for Tay- Sachs irrespective of the probability of their carrying the disease. In rejecting this claim, the judge noted that there were more than 70 tests that physicians would have had to offer to every patient to meet the plaintiff’s requirements. [Munro v. Regents of Univ. of Cal., 215 Cal. App.3d 977, 263 Cal. Rptr. 878 (Cal. App. 2d Dist. 1989).]
The American College of Obstetrics and Gynecology (ACOG) has established recommended procedures for taking genetic histories and diagnosing genetic diseases. [ACOG Technical Bulletin 108. Antenatal Diagnosis of Genetic Disorders. September 1987.] These are the starting point for all physicians providing general medical or obstetric care. The objective of this genetic history is to determine which women are at elevated risk for genetic disease. Once these women are identified, they can be referred to specialists in genetic diseases or managed by the treating physician if he or she has the necessary expertise.