The age association is highlighted by patient #5, the youngest SMA patient with 3 SMN2 copies, who at the age of 1 year with 34.50 pg/mL exhibited a considerably higher initial concentration than the other SMA patients with >2 SMN2 copies (4.29–23.60 pg/mL). The gene discussed is SMN2; the disease is proximal spinal muscular atrophy.