Diversidad genética de la raza equina marismeña

Abstract

Marismeño horse, is a Spanish equine breed threatened with extinction located almost exclusively at the Espacio Natural de Doñana, a protected area (Natural and National Park), at the Southwest of the Iberian Peninsula. To define the genetic profile of the breed, 25 microsatellites recommended by the International Society of Animal Genetics (ISAG) were analyzed: AHT4, AHT5, ASB17, ASB2, ASB23, HMS3, HMS6, HMS7, HTG10, HTG4, LEX3, LEX33, VHL20, TKY287, TKY294, TKY297, TKY301, TKY312, TKY321, TKY333, TKY337, TKY341, TKY343, TKY344, TKY394. The microsatellites were amplified by PCR (Polimerase Chain Reaction). The obtained fragments were separated by electrophoresis in an automatic sequencer ABI377XL (Applied Biosystems, Foster City, CA, USA). The fragment analysis and genotyping was made using the programmes Genescan Analisys 3.1.2 and Genotyper 2.5, using Genescan® 400HD ROX as size standard. Heterozigosity analysis, Fis, multivariate analysis and assignation and genetic structure analysis were performed. All the microsatellites analyzed were very informative and polymorphic, with a minimum of 6 alleles for the microsatellites AHT5, HMS6 and HMS7, and a maximum of 12 for the microsatellite ASB2. The Marismeño breed shows a high variability, with an average of 8,24 alleles per locus. The FIS value for the population is 0,007. This means that the population is homogeneous and not significantly deviated from HWE. The genetic structure analysis confirms the analysed individuals group together. The conclusion is that the first results of a great effort, done by the Marismeño horse breeders are being collected, to settle the breed characteristics without significant loss of genetic variability.