Short communication. Mitochondrial DNA diversity of the founder populations of the Asturcón pony

A 380 bp fragment of the horse D-loop region was analysed in 42 founder mare samples of the bay-coated Asturcon pony obtained in three different and reproductively isolated mountainous areas of Western Asturias: range of “La Bobia” (20), range of “Carondio” (13) and range of “El Aguion” (9). These sequences were compared with the information provided by 37 founder matrilines of black-coated Asturcon assigned to the range of “Sueve” (26) and the “out-of-Sueve” (11) founder populations. The aim of this research was to ascertain the differences in founder mtDNA diversity between the two strains of the Asturcon pony and if such differences have geographical consistency. The 79 sequences analysed gave 16 different haplotypes defined by 33 polymorphic sites. The two Asturcon strains shared eight haplotypes that gathered 76% and 81% of the samples available in bay-coated and black-coated Asturcon, respectively. Both haplotypic (0.027 ± 0.006) and nucleotide (0.021 ± 0.011) diversity were higher in the bay-coated than in the black-coated Asturcon (0.024 ± 0.005 and 0.016 ± 0.009, respectively). AMOVA analyses failed in assessing any statistically differentiation among Asturcon geographical populations or strains. Most genetic variability is due to the individuals (estimates varying from 96.34% to 99.81%). Differentiation among strains or population took low and non-significant values. Differentiation between Asturcon pony strains using mtDNA marker would not have clear support. The two strains of the Asturcon pony breed likely derive from the same ancestral mare population.