Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: NATIONAL ANIMAL GERMPLASM PROGRAM (NAGP)

Location: Plant And Animal Genetic Resources Preservation Research Unit

Title: Combining US and Brazilian microsatellite data for a meta-analysis of sheep (Ovis aries) breed diversity: Facilitating the FAO Global Plan of Action for conserving animal genetic resources

Authors
item Paiva, S -
item Mariante, A -
item Blackburn, Harvey

Submitted to: Journal of Heredity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 15, 2011
Publication Date: December 20, 2011
Citation: Paiva, S., Mariante, A., Blackburn, H.D. 2011. Combining US and Brazilian microsatellite data for a meta-analysis of sheep (Ovis aries) breed diversity: Facilitating the FAO Global Plan of Action for conserving animal genetic resources. Journal of Heredity. 102:697-704.

Interpretive Summary: Two problems were addressed in this research: 1. identification of a method to combine DNA markers evaluated in separate laboratories; and 2. what genetic differences exist between US and Brazilian sheep populations and how differences impact genetic management of national populations. The results indicate a statistical approach can be used to merge DNA datasets and thereby allow different countries to combine and analyze molecular data that has been acquired with substantial expense. Using this approach enabled Brazilian and US researchers to quantify the genetic distances and genetic variability among the sheep breeds. It was concluded that considerable genetic variability for sheep has been imported into both countries. Both countries hair sheep breeds were found to be genetically distinct; therefore breeders may wish to explore utilizing each others breeds to capitalize on potential hybrid vigor. In addition, the results are a tool to use by both countries conservation programs.

Technical Abstract: Microsatellites have been used to understand genetic diversity among livestock populations. Nevertheless, most studies have involved the processing of samples in one laboratory or with common standards across laboratories. Our objective was to identify an approach to facilitate the merger of microsatellite data for cross-country comparison of genetic resources when samples were not evaluated in a single laboratory. Eleven microsatellites were included in the analysis of 13 US and 9 Brazilian sheep breeds. A Bayesian approach, was selected and evaluated with and without a common set of samples analyzed by each country and all markers had a posterior probability of greater than 0.5. Sensitivity analysis indicated no difference between results with or without common samples. Cluster analysis, with STRUCTURE, suggests K values of 7 and 12 showed breeds to be partitioned by function (hair, meat, or wool type). Cross country comparison of hair breeds indicated substantial genetic distances and within breed variability. The selected approach can facilitate the merger and analysis of microsatellite data for cross-country comparison and extend the utility of previously collected molecular markers. Furthermore, the result of which can be used in new and existing country conservation programs.

Last Modified: 4/18/2014
Footer Content Back to Top of Page