A new drug is offering hope for the family of a little girl whose genetic defect causes mobility issues similar to that of polio and amyotrophic lateral sclerosis (ALS). Four-year-old Lexi Pacini, of Colorado Springs, was diagnosed with type 2 spinal muscular atrophy (SMA) as a toddler. The rare disease is marked by the absence of a gene that codes protein signals from motor neurons to muscles, and it leads muscles to weaken to the point of atrophy. **SNIP** “She dances the way she knows how, in her walker,” Tammy told Children’s Hospital Colorado in the release. “She just doesn’t...