Mitochondrial DNA Variations in Colombian Creole Sheep Confirm an Iberian Origin and Shed Light on the Dynamics of Introduction Events of African Genotypes

Abstract

The genetic origins and diversity of Creole sheep from five regions of Colombia were investigated based on mitochondrial DNA (mtDNA) variations across 89 sequences from five breeds: one wool Creole sheep (CL) and four hair Creole sheep, including Ethiopian (OPC_E), Sudan (OPC_S), Pelibuey (OPC_P) and Wayúu (OPC_W). A global comparison was done using 62 haplotypes from Iberian, African, Indian, Caribbean, Mexican, Caucasian and European sheep based on sequences retrieved from GenBank. This study aimed to identify the maternal origin of Colombian Creole sheep and their genetic relationships at a global level. The results showed 31 different haplotypes from Colombian Creole sheep, which can be assigned to maternal lineage B, the most common lineage found in European sheep breeds and the only one found in several Iberian breed (e.g., Churra, Spanish Merino) that most likely participated in the Creole formation. Additional analyses showed that wool and hair sheep retained a broad genetic identity despite being geographically separated. The global-level phylogenetic analysis revealed that Colombian Creole sheep belong to a distinct and defined genetic lineage that is likely the result of a founder effect with ecotypes of Iberian descent and the subsequent introduction of foreign breeds. This is consistent with historical reports on the presence of sheep in South America and, particularly, Colombia.

Keywords: Creole sheep; haplotype; maternal heritage; mitochondrial DNA.

Figure 1

Five breeds of Colombian Creole sheep analyzed in the study. (A) Ethiopian (OPC_E); (B) Sudan (OPC_S); (C) Pelibuey (OPC_P); (D) wool Creole sheep (CL); (E,F) Wayúu Creole sheep (OPC_W).

Figure 2

Map of the sampling locations of the five Colombian Creole sheep breeds and Ecuador sheep.

Figure 3

Pattern of 31 mtDNA control region haplotypes in Colombian Creole sheep constructed using the TCS program and plotted with tcsBU. Each haplotype is represented by a pie chart with size proportional to the number of sequences of each breed. The number of haplotypes corresponds to those indicated in Table 2 and Table S4. The small white circles indicate mutational changes. The five Creole breeds are indicated by the colors shown in the legend. CL—wool Creole; OPC_E—Ethiopian; OPC_S—Sudan; OPC_P—Pelibuey; OPC_W—Wayúu.

Figure 4

Phylogenetic tree inferred from maximum likelihood based on the analysis of 31 haplotypes found in five breeds of Colombian Creole sheep. Capra hircus (AB004082) was used as outgroup.

Figure 5

Pattern of 31 mtDNA haplotypes in Colombian Creole sheep and their genetic relationships with 62 reference haplotypes (Table S2). Each haplotype is represented by a circle with size proportional to the number of shared sequences; the small white circles indicate mutational changes and each country or breed are color-coded according to the legend. Reference lineages are listed as Ref, while the Colombian haplotypes are listed h1–h31.