COL2A1 and scoliosis: Developmental SHP2 deletion in COL2α1+ chondrocytes caused midgestation lethality (around E11.5), but postnatal SHP2 deletion in the same cell population led to scoliosis, expansion of the growth plate cartilage affecting both proliferating and hypertrophic chondrocytes, chondrodysplasia, enchondromas, exostoses, and reduced bone mineral density.