[MIM*118600] a disease characterized by deposits of calcium pyrophosphate crystals free of urate in synovial fluid, articular cartilage, and adjacent soft tissue; causes various forms of arthritis commonly characterized by goutlike painful attacks, swelling of joints, and radiologic evidence of calcification in articular cartilage (pseudogout); inherited as an autosomal dominant trait in some cases, and associated with certain diseases in others. An inherited autosomal dominant form is caused by a mutation in the human ankylosis gene (ANKH).