Hereditary pyrophosphate arthropathy (familial articular chondrocalcinosis) in Sweden.
Genealogical links between three Swedish families with hereditary pyrophosphate arthropathy were found in the 18th century, indicating a possible founder effect, similar to earlier findings in Slovakia, France and Chile. However, no connection between the Swedish and other European families with the disease has so far been found. In accordance with other reported familial aggregations of pyrophosphate arthropathy, the transmission of the disease in the Swedish families appeared to be autosomal dominant with incomplete penetrance and variable expressivity. Severe symptoms related to homozygotic cases reported in some other families were not found in Sweden.