FN1 and osteoarthritis: 1. Neurological disorders: Neuron-specific aberrant AS causes protein dysfunction (e.g., in SMA, AS defects in SMN2 result in insufficient functional SMN protein).2. Osteoporosis: AS of RUNX2, YBX1, and SRSF1 affects bone mass and the balance between osteogenic and adipogenic differentiation.3. Osteoarthritis: Variants of FN1, PLOD2, and CALCA regulate cartilage degradation and osteophyte formation.4. Hereditary bone diseases: Splicing mutations in COL1A1/2, TMEM38B, PHEX, and TCIRG1 directly cause disease.