Genetic characterization and polymorphisms for parentage testing of the Jeju horse using 20 microsatellite loci.

The research provides a thorough genetic examination of the Jeju horse, a breed from South Korea. Using 20 unique genetic markers, the study confirms a high degree of genetic diversity within the Jeju horse population, establishing a solid foundation for accurate pedigree construction and future conservation programs.

Genetic Characterization and Microsatellite Loci

• The aim of the research was to conduct a genetic characterization of the Jeju horse. This was done by genotyping 111 horses, including 79 Jeju horses.
• The genotyping involved 20 different microsatellite loci, which are DNA sequences made up of repeating units of 1 to 6 base pairs. These loci form the basis for determining an organism’s genetic characteristics.
• The number of alleles (different forms of a gene found at the same place on a chromosome) at the 20 loci studied varied from 5 to 11, averaging 7.45. This indicates a considerable genetic diversity within the Jeju horse population.

Observed and Expected Heterozygosity

• Heterozygosity is a measure of genetic variation within a population. Observed heterozygosity refers to the proportion of individuals in a population that are heterozygous, having two different forms of a particular gene.
• In this study, the observed heterozygosity ranged from 0.293 to 0.891, indicating that a significant portion of the Jeju horses are heterozygous. This variety contributes to the genetic diversity of the population.
• Expected Heterozygosity, on the other hand, refers to the heterozygosity that would be expected under random mating given allele frequencies. In the Jeju horse, it ranged from 0.357 to 0.841.

Polymorphic Information Contents and Exclusion Probability

• Polymorphic Information Contents (PIC) were calculated for each microsatellite, ranging from 0.335 to 0.816, with ten loci exhibiting relatively high PIC values. The PIC value works as a measure of genetic diversity, indicating each marker’s usefulness for genetic linkage studies.
• The total exclusion probability (PE), which refers to the chance of excluding a falsely accused parent, was 0.9999, indicating a high reliability of the genotyping process for parentage verification among Jeju horses.

Implications for Jeju Horse Conservation

• The results are crucial for developing accurate pedigrees. A pedigree charts an individual’s ancestors, used to assess the individual’s genetic diversity. An accurate pedigree can reveal the potential risks and benefits of mating certain individuals.
• With high genetic diversity within the Jeju horse population, the study provides essential information for making informed decisions regarding their conservation, ensuring the long-term survival and health of the breed.