Newborn and carrier screening for spinal muscular atrophy

TLDR

Spinal muscular atrophy is a common autosomal recessive neuromuscular disorder caused by SMN1 mutations, affecting about 1 in 10,000 live births, and while no definitive therapy exists, accurate diagnosis—including newborn screening and carrier testing—is essential for early intervention and reproductive decision‑making. The study aims to identify couples at risk for SMA through population‑based carrier screening to enable informed reproductive choices. The authors conducted two pilot projects to assess the clinical applicability of newborn SMA screening and general population carrier testing. The pilots demonstrated that effective newborn screening technology exists, provided an estimate of carrier frequency among screened individuals, and revealed patients’ knowledge and attitudes toward SMA testing. © 2010 Wiley‑Liss, Inc.

Abstract

Abstract Spinal muscular atrophy (SMA) is a common autosomal recessive neuromuscular disorder caused by mutations in the survival motor neuron ( SMN1 ) gene, affecting approximately 1 in 10,000 live births. The homozygous absence of SMN1 exon 7 has been observed in the majority of patients and is being utilized as a reliable and sensitive SMA diagnostic test. Treatment and prevention of SMA are complementary responses to the challenges presented by SMA. Even though a specific therapy for SMA is not currently available, a newborn screening test may allow the child to be enrolled in a clinical trial before irreversible neuronal loss occurs and enable patients to obtain more proactive treatments. Until an effective treatment is found to cure or arrest the progression of the disease, prevention of new cases through accurate diagnosis and carrier and prenatal diagnosis is of the utmost importance. The goal of population‐based SMA carrier screening is to identify couples at risk for having a child with SMA, thus allowing carriers to make informed reproductive choices. During this study we performed two pilot projects addressing the clinical applicability of testing in the newborn period and carrier screening in the general population. We have demonstrated that an effective technology does exist for newborn screening of SMA. We also provide an estimate of the carrier frequency among individuals who accepted carrier screening, and report on patient's knowledge and attitudes toward SMA testing. © 2010 Wiley‐Liss, Inc.