Genetic diversity of North Ethiopian indigenous sheep populations using mitochondrial DNA

Abstract: This study was aimed to investigate the haplotype variations and maternal origin of four sheep populations (Highland, Abergelle, Elle and Begait) of North Ethiopia. A 1088 bp of the mtDNA control region was amplified using specific primers and the polymerase chain reaction was performed. The PCR products were purified and sequenced. Control region of the 24 mtDNA samples was sequenced. For the haplotype diversity, 1088 bp of the d-loop region of the indigenous sheep populations was analysed. Whereas, to define the maternal origins, 517 bp of mtDNA D-loop region aligned to sequences of globally defined reference sequences was used. A total of 21 haplotypes were defined from 97 segregating sites. The number of segregating sites (s) were varied among the four sheep populations. The s value of Highland, Abergelle, Begait and Elle sheep populations were (75, 19, 22 and 16 respectively). Highland sheep population had higher number of haplotypes (13) than Abergelle, Begait and Elle (4, 3 and 3 respectively). The average number of nucleotide differences (Kt) is (13.11594). Highland, Begait and Elle sheep have higher haplotype diversity values (1) than Abergelle sheep (0.9). The nucleotide diversity (π) of Abergelle sheep also reveal the same tendency (0.0082), being lower than the π value of Elle, Begait and Highland (0.0106, 0.0146 and 0.0150, respectively). The AMOVA analysis indicates 29.78% variation explain variations among the 4 populations. The phylogenetic network analysis clustered the detected haplotypes into two haplogroups, haplogroup A and B which are separated by 13 mutational sites. The mismatch analysis shows the presence of a one-time demographic expansion. Having rich matrilines in those indigenous sheep populations is essential for future conservation and breeding programmes.