Chondrocalcinosis 2 is a rare disease characterized by the accumulation of calcium pyrophosphate dihydrate (CPP) crystals in and around the joints. Signs and symptoms of the disease include chronic joint pain or sudden, recurrent episodes of pain, as well as stiffness or swelling of the joints. Chondrocalcinosis 2 is actually a familial form of chondrocalcinosis (also known as calcium pyrophosphate deposition disease or CPPD), which is caused by a similar buildup of CPP crystals but is associated with the aging process. Chondrocalcinosis 2 is caused by changes in the ANKH gene. The disease is inherited in an autosomal dominant manner. Chondrocalcinosis 2 is diagnosed based on imaging such as X-rays. The diagnosis can be confirmed with genetic testing of the ANKH gene.