Hypophosphatasia (HPP) is a rare genetic metabolic bone disorder with highly variable severity; severe pediatric forms are very uncommon (around 1 in 100,000 births), while milder adult forms are likely more frequent and often go undiagnosed. HPP is most commonly caused by mutations in the ALPL gene, leading to deficiency of tissue-nonspecific alkaline phosphatase and impaired bone and tooth mineralization. This can result in rickets or osteomalacia, frequent or stress fractures, skeletal deformities, premature tooth loss, muscle weakness, and joint complications such as chondrocalcinosis. Many people with HPP experience pain, fatigue, and other impacts on daily functioning and emotional wellbeing.