Illinois Expands Newborn Screening to Include SMA
The addition of SMA — the 49th disorder in the state’s screening program — means that every baby born in Illinois will be tested for the autosomal recessive neurodegenerative disease that affects one in every 8,000 to 10,000 people worldwide.
“Spinal Muscular Atrophy is a disease that robs people of physical strength, including the ability to walk, eat, or breathe,” Ngozi Ezike, MD, director of the IDPH, said in a press release. “It is the number one genetic cause of death for infants. Early diagnosis of babies with SMA can lead to potentially life-saving interventions. By screening every baby born in Illinois, we hope to identify cases early so therapy can begin as soon as possible,” she said.
SMA is characterized by progressive muscle weakness caused by the loss of specialized nerve cells — motor neurons — in the spinal cord and the part of the brain connected to the spinal cord. Because motor neurons control voluntary muscle movements, their loss leads to muscular weakness and atrophy. Movement becomes increasingly slower, and the ability to control voluntary movement ultimately may be totally lost.
Starting treatment early is the only way to prevent motor neuron loss. In fact, infants identified as having SMA should begin therapy before SMA symptoms appear. Currently, Biogen’s Spinraza and the gene therapy Zolgensma, developed by Novartis subsidiary AveXis, are the only disease-modifying SMA treatments available. Other medications aim to manage SMA symptoms or prevent complications. Several experimental therapies also are being developed.
In 2018, SMA was added to the federal Recommended Uniform Screening Panel for newborn testing (RUSP). The RUSP is a list of disorders the U.S. Department of Health and Human Services recommends for states’ universal newborn screening programs. Such disorders are chosen based on evidence that supports the potential net benefit of screening, the ability of states to screen for them, and the availability of effective therapies.
In preparation for adding SMA to its screening program, the IDPH bought new equipment, developed new test methods, and modified computer systems to provide lab results and facilitate follow-up tracking.
The agency also obtained test validation from the federal Clinical Lab Improvement Amendments (CLIA). The CLIA regulate laboratory testing and require clinical labs to be certified by the Centers for Medicare and Medicaid Services before they can accept human samples for diagnostic testing.
Newborn screening for SMA tests for the presence of the survival motor neuron 1 (SMN1) gene. If testing results reveal that the gene is absent or markedly reduced in signal, immediate referral will be made to a pediatric multidisciplinary neuromuscular center for diagnostic testing and evaluation. This site has for more information.
Still, screening newborns for genetic diseases that have therapies that can prevent disease progression has a long way to go in the U.S. As it is, no state currently tests for all 35 disorders federally recommended, and even those that come close can be hamstrung by competing interests and obligations. Each state decides the scope of its newborn screenings.
The 2019 approval of Zolgensma — Spinraza has been on the market since 2016 — sparked a push among some scientists, physicians, and patient advocates to have all babies around the world tested for the disease.