Wilfond B S, Fost N
Department of Pediatrics, University of Wisconsin School of Medicine, Madison.
JAMA. 1990;263(20):2777-83.
The primary goal of mass screening programs for cystic fibrosis carriers should be to allow people to make more informed reproductive decisions. However, previous experience with genetic screening programs, including those for phenylketonuria and sickle cell disease, have revealed complex problems including error, confusion, and stigmatization. These problems could be greater with cystic fibrosis, since more than 8 million Americans may be carriers and entrepreneurial interests can be expected to promote screening in what could become a billion-dollar industry. The present frequency of the detectable mutation (delta F508), 75%, will complicate the counseling process. The sensitivity of the test to detect at-risk couples would be 56%. The cost of screening could be as much as $2.2 million for each cystic fibrosis birth avoided. Regardless of improvements in the detection rate, implementation of population screening should be delayed until pilot studies that demonstrate its safety and effectiveness are completed. While studies are in progress, preconception testing should be offered to adult relatives of cystic fibrosis patients as part of a comprehensive program following institutional review board approval for "compassionate use." The purpose of such review should be to ensure that strict standards of informed consent, education, quality control of the testing procedure, and counseling are followed. Primary care physicians who are unable to offer screening as part of such a comprehensive program should refer high-risk patients who would like to consider being tested to established centers.
囊性纤维化携带者群体筛查项目的主要目标应该是让人们能够做出更明智的生育决策。然而，以往基因筛查项目的经验，包括苯丙酮尿症和镰状细胞病的筛查项目，都暴露出了一些复杂问题，如误差、困惑和污名化。对于囊性纤维化来说，这些问题可能会更严重，因为超过800万美国人可能是携带者，商业利益可能会推动筛查，这有可能成为一个价值数十亿美元的产业。目前可检测突变（ΔF508）的频率为75%，这会使咨询过程变得复杂。该检测识别高危夫妇的敏感度为56%。每避免一例囊性纤维化患儿出生，筛查成本可能高达220万美元。无论检测率有何提高，在证明其安全性和有效性的试点研究完成之前，都应推迟实施人群筛查。在研究进行期间，经机构审查委员会批准“同情用药”后，作为综合项目的一部分，应为囊性纤维化患者的成年亲属提供孕前检测。此类审查的目的应是确保遵循严格的知情同意、教育、检测程序质量控制和咨询标准。无法作为此类综合项目一部分提供筛查的初级保健医生，应将希望接受检测的高危患者转诊至成熟的中心。
