40% of patients with SMA type 1 had a gastrostomy tube and, of these, 84% had two copies of SMN2. The correlation between copy number and the need for gastrostomy was not statistically significant, however, patients with three copies (10–21 years) might have been influenced by other factors, such as late initiation of treatment, as well as greater disease progression at the time the gastrostomy procedure took place. This evidence concerns the gene SMN2 and spinal muscular atrophy, type 1.