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[Lafora disease and founder effect in a small neotropical locality]
1Escuela de Biología, Universidad de Costa Rica, San José, Costa Rica. msolis@biologia.ucr.ac.cr
Revista De Biologia Tropical
|May 17, 2001
Summary
Lafora disease, a rare genetic disorder, affected four individuals in Zarcero, Costa Rica, due to a founder effect from common ancestors. This genetic drift highlights the impact of isolated populations on rare disease prevalence.
Area of Science:
- Neurology
- Genetics
- Epidemiology
Context:
- Lafora disease is a rare, fatal, autosomal recessive neurodegenerative disorder.
- Four cases were identified in Zarcero, Costa Rica, a small, isolated community.
- The cases originated from two consanguineous families with shared ancestry.
Purpose:
- To report and analyze the occurrence of Lafora disease in an isolated population.
- To investigate the genetic origins and transmission of Lafora disease in this community.
Summary:
- Diagnosis was confirmed via liver biopsy in one patient.
- Onset ages ranged from 13 to 17 years, with rapid physical and mental decline.
- The disease gene was traced to the town's founders, illustrating a founder effect.
Impact:
- This study provides a unique example of genetic drift and founder effect in a rare genetic disease.
- Understanding the prevalence and transmission in isolated populations is crucial for genetic counseling and research.
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