Bioethics Blogs

Spotlight on Non-Invasive Prenatal Testing

Chris Kaposy suggests that Canada should learn from the United States’ failure to regulate the industry for Non-Invasive Prenatal Testing.

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Non-Invasive Prenatal Testing to detect genetic conditions in fetuses is a growing industry. Originally developed to screen traces of cell-free fetal DNA in the blood of pregnant women for the purpose of identifying fetuses with Down syndrome, Non-Invasive Prenatal Testing kits are now available for trisomies 13, and 18, sex chromosome aneuploidies, and a myriad of sub-chromosomal deletions that cause conditions such as Prader-Willi/Angelman syndrome, Wolf-Hirschhorn syndrome, and Jacobsen syndrome.

I recently co-authored an article in the journal Prenatal Diagnosis that details some of the impact of this expansion of prenatal testing on American groups that advocate for persons with the genetic conditions detected by this new form of prenatal testing. Advocacy group members, some of whom participated in writing the article, suggest that the development and the expansion of Non-Invasive Prenatal Testing have occurred without sufficient regulatory oversight in the United States, and without adequate genetic counselling resources.

The early industry-funded studies into Non-Invasive Prenatal Testing for Down syndrome related that these tests demonstrated a high degree of sensitivity (an ability to successfully identify fetuses with Down syndrome) and specificity (an ability to correctly identify fetuses without Down syndrome). Subsequent studies by independent researchers and clinics, however, were less definitive than the initial industry-based studies. These studies noted several problems including false positives, questions about positive predictive value, and other test limitations. Nonetheless, tests for rarer conditions such as genetic microdeletions were introduced to the American market with less supporting data than originally provided for Down syndrome testing.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.