Spinal Muscular Atrophies of ChildhoodMuscular Atrophy, SpinalSurvival of Motor Neuron 1 ProteinSMN Complex ProteinsSurvival of Motor Neuron 2 ProteinAtrophyMuscular AtrophySpinal CordNeuronal Apoptosis-Inhibitory ProteinCyclic AMP Response Element-Binding ProteinMotor NeuronsRNA-Binding ProteinsAnterior Horn CellsMuscular Disorders, AtrophicBulbo-Spinal Atrophy, X-LinkedNerve Tissue ProteinsSpinal Cord InjuriesRibonucleoproteins, Small NuclearDEAD Box Protein 20Chromosomes, Human, Pair 5ExonsSpinal Cord DiseasesCoiled BodiesMotor Neuron DiseasesnRNP Core ProteinsDisease Models, AnimalOptic AtrophyPedigree