The Changing Moral Focus of Newborn Screening: An Ethical Analysis by the President's Council on Bioethics
The President's Council on Bioethics
What ethical principles should guide the practice of newborn screening in the United States ? That question is the starting point for this white paper by the President's Council on Bioethics. It has been a serious question since newborn screening began over four decades ago; in recent years, however, it has taken on new urgency in light of significant and ongoing changes in the practice of newborn screening. In this white paper, the Council analyzes these changes and their ethical implications.
The great majority of babies born in the United States each year1 undergo screening soon after birth to identify genetic defects that could cause serious illness if left undetected and untreated. The goal is to detect diseases as early as possible so that timely, effective treatment can be initiated even before the onset of symptoms. In most states, newborn screening is now mandated by law. The number of conditions screened for by state health departments has expanded considerably since the 1960s, when microbiologist Robert Guthrie invented the heel-stick blood test for phenylketonuria (PKU). In the United States today, almost all infants are screened at birth for between thirty and fifty genetic disorders, depending on the screening program of the state in which they are born. Of the approximately four million babies screened each year, about 5,000 are identified as having serious heritable disorders, most of which are, in varying degrees, amenable to treatment.2
Newborn screening has produced undeniable benefits: for example, PKU—which causes severe, irreversible mental retardation if left untreated—is one of the few genetic diseases whose symptoms can be controlled by a restricted diet, and newborn screening identifies about 200 infants with PKU in the United States every year. Another notable success story has been the early detection of congenital hypothyroidism (CH), whose symptoms—including abnormal growth and mental retardation—can easily be controlled with a daily dose of thyroid hormone; newborn screening for CH, initiated in the 1970s, now detects over 1,000 cases of CH in the United States each year. In the wake of these and other achievements, more and more disorders have been added to state-mandated newborn screening programs. Today, we routinely screen infants for dozens of rare genetic disorders, including some whose medical implications are not clearly understood and for which effective treatments are not yet available.
Traditionally, a population screening program (whether for children or for adults) has been considered justifiable only if the targeted condition is an important health problem, whose natural history is well-understood, and whose symptoms are amenable to early intervention and effective treatment. On this view, the object of screening is to discover those among the apparently well who are in fact suffering from disease, in order to initiate timely and effective treatment. Accordingly, the mere availability of a reliable test would not justify routine screening for a condition, unless such screening could be shown to provide direct medical benefit to those who test positive for the condition. In short, for more than forty years the moral focus of newborn screening has been what is good for the infant .
As more and more disorders have been added to state newborn screening programs, however, the traditional ethical principles of screening have been called into question. Some have argued that the central criterion of direct medical benefit to the infant need not be strictly satisfied in order to justify routine screening for a condition; according to this view, a broader conception of benefit —including benefits to the family and to society at large as well as indirect benefits to the child—justifies screening even for conditions that are poorly understood or that do not, as yet, have an effective treatment. Others have argued that all (or almost all) conditions that can be detected should be screened for at birth—reasoning that such screening is the most effective way to gain knowledge of and find treatments for diseases that are rare, poorly understood, and at present untreatable. According to both of these positions, newborn screening should be considered an appropriate tool of biomedical research , which benefits society as a whole by increasing our knowledge of rare diseases and, ultimately, our ability to treat them.
The aim of the present white paper is to foster public awareness of the practice of newborn screening, the ethical principles that have guided it until now, and the ethical problems posed by its current and future expansion. The white paper consists of four chapters. In the first chapter , we describe the current practice of newborn screening in the United States : how a blood sample is taken from each infant at birth, how the blood is tested for heritable disorders, and what is done with the information gleaned from those tests. We also identify some of the ethical challenges that confront us as we try to reap the benefits of newborn screening while minimizing the harms. Finally, we explain the public policies that shape the practice of newborn screening in the United States . In the second chapter , we explain the ethical principles that have guided the practice of newborn screening for the past forty years, and we consider whether those ethical principles have been altered or abandoned by the new regime of expanded newborn screening that is currently being adopted by most states. In the third chapter , we attempt to envision the future of newborn screening, examining the ethical implications of the vast expansion of newborn screening that can be anticipated as the age of personalized genomic medicine advances. Finally, in the fourth chapter , we take up the urgent question of whether the states should have mandatory screening programs (as most currently do), elective programs, or some combination of the two. We close this chapter and the white paper as a whole by recommending an ethical framework for a sound newborn screening policy in the United States —a framework that we believe to be not only appropriate for the present phase of newborn screening but also valuable for addressing future medical and technological advances in newborn screening.
1. More than ninety-eight percent in 2008, according to the Centers for Disease Control and Prevention's Division of Laboratory Sciences. See www.cdc.gov/nceh/dls/newborn.htm.