Newborn screening for spinal muscular atrophy in Japan: One year of experience

Spinal muscular atrophy (SMA) is a degenerative neuromuscular disease that causes progressive muscle weakness and atrophy due to loss of the anterior horn cells of the spinal cord. Although effective treatments, such as gene therapy, have emerged in recent years, their therapeutic efficacy depends on a restricted time window of treatment initiation. For the treatment to be effective, it must be started before symptoms of the disease emerge. For this purpose, newborn screening (NBS) for SMA is conducted in many countries worldwide. The NBS program for SMA has been initiated in Japan in several regions, including the Kumamoto Prefecture. We started the NBS program in February 2021 and detected a patient with SMA after screening 13,587 newborns in the first year. Herein, we report our experience with the NBS program for SMA and discuss an issue to be approached in the future.