Development of Microsatellites for the Philippine Eagle, Pithecophaga jefferyi, Using Next-generation Sequencing

Perry S. Ong1†, Vonette Joi B. Padilla1, Marco Philip B. Serafica1, Adrian U. Luczon1, Dennis Joseph I. Salvador2, Melizar V. Duya1, Ian Kendrich C. Fontanilla1, and Jonas P. Quilang1*

1Institute of Biology, University of the Philippines Diliman
Quezon City, Metro Manila 1101 Philippines
2Philippine Eagle Foundation, Davao City, Davao Del Sur 8000 Philippines
†Deceased 02 Mar 2019

*Corresponding Author: This email address is being protected from spambots. You need JavaScript enabled to view it.eThis email address is being protected from spambots. You need JavaScript enabled to view it.





The Philippine Eagle, Pithecophaga jefferyi, is a critically endangered bird of prey that is endemic to the dipterocarp forests of the Philippines. In this study, data from next-generation sequencing (NGS) were used for the development of microsatellites for the Philippine Eagle. A total of 49,965 microsatellite loci were predicted and 20,960 primer pairs were designed. Forty (40) of these pairs were synthesized and were tested on 20 captive individuals. Twenty (20) of these markers showed high amplification success rates and exhibited polymorphism. A maximum of 24 alleles was detected across the 20 markers with an average of 13.9 alleles, which is remarkably higher than other microsatellite studies in eagles. The resulting values for observed heterozygosity (Ho) ranged from 0 to 1.00 with an average of 0.290, while expected heterozygosities ranged from 0.791 to 0.968 with an average of 0.910.

The Philippine Eagle, Pithecophaga jefferyi Ogilvie-Grant 1896, occurs primarily in the steep terrains and heavy forests of the four islands in the Philippines: Luzon, Samar, Leyte, and Mindanao (Bueser et al. 2003). The Philippine Eagle has a small and rapidly decreasing population due to extensive deforestation and is classified as a critically endangered species. Owing to the increasing concern over the endangered status of the Philippine Eagle, studies have been initiated across the country to investigate the bird’s genetic background. DNA barcodes from 43 individuals of six species of captive Accipitrids, including 31 individuals of Philippine Eagle found in the Philippine Eagle Center (PEC), were reported by Ong et al. (2011). Luczon et al. (2014) determined the genetic diversity of 22 individuals of Philippine Eagle (19 of which came from the wild and 3 were captive-bred) using mitochondrial control region. However, a more thorough knowledge of its genetic diversity is needed to provide more insights into the management and conservation of the species. . . . read more



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