Spinal muscular atrophy - Incidence in Iceland

Spinal muscular atrophy (SMA) is among the commonest degenerative disorders of the nervous system in childhood. This is an inherited autosomal recessi ve disease which results in premature death of anterior horn cells of the s pinal cord and is manifested by progressive weakness and atrophy of skeleta l muscles. Few studies have looked at the frequency of the disease in a def ined population. We identified all patients diagnosed with SMA in Iceland d uring a 15-year period. The diagnosis is based on typical symptoms and supp orted by results of electromyography/nerve conduction studies and muscle bi opsy. The average annual incidence was 13.7 per 100,000 live births for all types of SMA, which is similar to that reported in other population-based studies.