Related Experiment Videos
Trans-ethnic fine mapping of a quantitative trait locus for circulating angiotensin I-converting enzyme (ACE)
C A McKenzie1, G R Abecasis, B Keavney
1Tropical Metabolism Research Unit, University of the West Indies, Kingston 7, Jamaica. camcken@uwimona.edu.jm
Human Molecular Genetics
|May 2, 2001
Summary
Genetic studies reveal that circulating angiotensin I-converting enzyme (ACE) levels are linked to the ACE gene. Comparing Jamaican and British families identified ethnic differences in genetic associations influencing ACE levels.
Area of Science:
- Genetics
- Molecular Biology
- Population Genetics
Background:
- Circulating angiotensin I-converting enzyme (ACE) levels are influenced by a quantitative trait locus (QTL) linked to the ACE gene.
- Previous studies suggested the QTL is downstream of an ancestral breakpoint, but linkage disequilibrium hindered resolution in Caucasian subjects.
Purpose of the Study:
- To investigate ACE gene polymorphisms and their association with circulating ACE levels in Afro-Caribbean families from Jamaica.
- To compare genetic associations between Jamaican and British Caucasian families to identify ethnic differences in QTL resolution.
Main Methods:
- Examined 10 ACE gene polymorphisms in Jamaican families.
- Utilized variance components analyses to assess linkage and association with circulating ACE levels.
- Contrasted results with a dataset from British Caucasian families.
Main Results:
- Strong evidence of linkage and association between ACE gene markers and circulating ACE levels was found in Jamaican families.
- Allelic association patterns differed significantly between Jamaican and British Caucasian families.
- In British families, three markers were in complete disequilibrium with the ACE-linked QTL; in Jamaican families, only one marker showed strong but incomplete disequilibrium.
Conclusions:
- Suggests additional unobserved polymorphisms influence circulating ACE levels in Jamaican families.
- Highlights the utility of variance components analysis and cross-ethnic comparisons for fine-mapping QTLs.
- Demonstrates the importance of considering population-specific genetic factors in quantitative trait association studies.