Parentage testing of Thoroughbred horse in Korea using microsatellite DNA typing

The present study was to construct a parentage testing system for Thoroughbred (TB) horse. A total number of 1,285 TB horse samples including 962 foals for parentage testing, 9 sires and 314 dams for individual identification were genotyped. Genomic DNA was extracted from 5 hair roots and genotyped by using 14 microsatellite markers (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS3, HMS6, HMS7, HTG4, HTG10, LEX3 and VHL20). This method consisted of multiplexing PCR procedure and showed reasonable amplification of all PCR products. Genotypes were determined by genetic analyzer. The number of alleles per locus varied from 3 to 9 with a mean value of 6.36 in TB horse. The expected heterozygosity was ranged from 0.548 to 0.831 (mean 0.699), and the total exclusion probability of 14 microstellite loci was 0.9998. Of the 14 markers, ASB2, ASB17, ASB23, HMS7 and HTG10 loci have relatively high PIC value (> 0.7). Of the 962 foals, 960 foals were qualified by compatibility according to the Mendelism. These results suggest that the DNA typing method has high potential for parentage verification and individual identification of TB horses.