genetic disorder causing poor bone development despite normal vitamin D levels
Hereditary Vitamin D Resistant Rickets (HVDRR) is a rare genetic disorder where the body is unable to properly respond to vitamin D, leading to poor bone development and rickets despite normal or high levels of vitamin D in the blood. This condition is caused by mutations in the vitamin D receptor (VDR) gene, which impairs the body's ability to absorb calcium and phosphate, essential for healthy bone formation.