Spinal muscular atrophy (SMA) is a genetic disease affecting the central nervous system, peripheral nervous system, and voluntary muscle movement (skeletal muscle).
In the most common form of SMA (chromosome 5 SMA, or SMN-related SMA), there is wide variability in age of onset, symptoms, and rate of progression. In order to account for these differences, chromosome 5-related SMA, which often is autosomal recessive, is classified into types 1 through 4.
SMA varies in severity, mostly because people have different levels of a “back-up” gene called SMN2. This gene is not as effective as SMN1, but people with SMA rely on it because their SMN1 gene does not work. More copies of SMN2 are linked to a milder form of the disease.
Two methods for SMA New Born Screening (NBS) use dried blood spot (DBS) samples in a Real-Time PCR (RT-PCR) assay to detect a homozygous SMN1 exon 7 deletion which is responsible for >95% of SMA. Here we assessed the technical feasibility of using next-generation DNA sequencing (NGS) as an alternate method for NBS programs to screen for SMA.
