Familial chondrocalcinosis in the Chiloe Islands, Chile
Annals of the Rheumatic Diseases
|June 1, 1975
Summary
Chondrocalcinosis, a genetic disorder, is highly prevalent in Chiloe Islands families, suggesting a rare recessive inheritance pattern. Elevated pyrophosphate levels in synovial fluid indicate a potential biochemical marker for this condition.
Area of Science:
- Genetics
- Biochemistry
- Epidemiology
Background:
- Chondrocalcinosis exhibits high frequency and familial aggregation in the Chiloe Islands.
- Previous observations suggested a genetic basis for the disease in this population.
Purpose of the Study:
- To investigate the inheritance pattern and potential origin of chondrocalcinosis in the Chiloe Islands.
- To identify biochemical alterations associated with the disease.
Main Methods:
- Analysis of family pedigrees and consanguinity.
- Anthropological assessment of patients.
- Biochemical analysis of synovial fluid.
Main Results:
- Recessive inheritance pattern strongly suggested by pedigree data and consanguinity.
- Evidence points to a Caucasian origin of the mutation, with documented ancestry to 1600.
- Significantly elevated pyrophosphate concentration in synovial fluid of affected individuals.
- No significant differences in calcium, phosphorus, or alkaline phosphatase levels compared to controls.
Conclusions:
- Chondrocalcinosis in the Chiloe Islands likely results from a rare recessive mutation of Caucasian origin.
- Elevated synovial fluid pyrophosphate is a key biochemical finding in this condition.
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