Hypophosphatasia (HPP) is a rare, systemic, inherited, metabolic disease caused by deficient activity of the tissue non-specific isoenzyme of alkaline phosphatase (TNSALP), resulting in the extracellular accumulation of its substrates - inorganic pyrophosphate (PPi), pyridoxal-5-phosphate (PLP) and phosphoethanolamine (PEA) [1]. Here, ALPL is linked to hypophosphatasia.