Genetic characterization of Egyptian and Italian sheep breeds using mitochondrial DNA.

A 721-bp fragment from 15,541 to 16,261 bp (NC_001941.1) of the mtDNA control region from different Egyptian and Italian sheep breeds was amplified. The PCR products were purified and sequenced. From the amplified fragment of 721-bp, a region of 423 bp after excluding a central region rich in tandem repeats was analyzed. Within all tested breeds, the haplotype diversity and average number of pairwise differences were 0.97571 and 7.01484, respectively. The genetic distances (D) and the average number of pairwise differences (Dxy) between breeds were estimated. The lowest distance was observed between Laticauda and Italian Muflon followed by distance between Sarda and Italian Muflon while the highest distance was observed between Barki and Sarda followed by distance between Barki and Laticauda. Phylogenetic analysis showed the presence of three haplogroups - HapA, HapB and HapC - in the examined samples with the absence of other two haplogroups HapD and HapE. All Italian samples cluster with B haplogroup and also in the Egyptian breeds the most dominant haplogroup was B (62 out of 67 analyzed samples). In Egyptian Barki breed one individual clusters with A haplogroup and another individual with C haplogroup. In Ossimi breed two individuals cluster with C haplogroup and in Rahmani there is one sample belonging to A haplogroup. The matrix of pairwise differences among breeds was used to perform a Principal Component Analysis (PCA). This analysis showed that the Italian breeds are clearly separated from the Egyptian breeds; moreover the Egyptian Barki breed is separated from Ossimi and Rahmani.