LINKAGE OF EARLY-ONSET OSTEOARTHRITIS AND CHONDROCALCINOSIS TO HUMAN-CHROMOSOME 8Q

Calcium pyrophosphate-deposition disease (CPDD), also called ''chondro calcinosis'' or ''pseudogout,'' is a disorder characterized by the dep osition of calcium-containing crystals in joint tissue, which leads to arthritis-like symptoms. The presence of these crystals in joint tiss ue is a common finding in the elderly, and, in this population, there is a poor correlation with joint pain. In contrast, early-onset CPDD h as been described in several large families in which the disease progr esses to severe degenerative osteoarthritis (OA). In these families, a n autosomal dominant mode of inheritance is observed, with an age at o nset between the 2d and 5th decades of life. In this report, we descri be a large New England family with early-onset CPDD and severe degener ative OA. We found genetic linkage between the disease in this family and chromosome 8q, with a multipoint lod score of 4.06. These results suggest that a defective gene at this location causes the disease in t his family.