Abstract:
The archaeological evidence suggests that Iran has
been one of the first origins of sheep
domestication in the world. This study aims to inve
stigate the genetic diversity of
indigenous Iranian sheep breeds using mitochondrial
DNA (mtDNA) and to explore the
evolutionary history of sheep domestication in Iran
. Single Nucleotide Polymorphism
(SNP) markers in the control region of mtDNA were u
sed to genotype the unrelated sheep
samples of Zel and Lori-Bakhtiari breeds which were
collected from or near the center of
the sheep domestication, using the Sequenom MassARR
AY platform. Phylogenetic
analysis of the mitochondrial SNPs classified all a
nimals into either of two haplogroups A
and B. The population differentiation (F
ST
) and gene flow (N
m
) statistics were 0.054 and
4.715 respectively, indicating a low mitochondrial
genetic differentiation and high gene
flow between two sheep breeds. The Analysis of Vari
ation (AMOVA) showed that around
97% of the total genetic diversity is distributed w
ithin the two breeds. Further analysis
using SNP haplotyping identified nine different hap
lotypes within the animals; eight
haplotypes were present in the Zel, while only four
were seen in the Lori-Bakhtiari breed.
Two haplotypes, designated H
1
and H
3
, were present at higher frequencies in both breeds
.
Haplotyes H
5
, H
6
, H
7
, H
8
and H
9
were found as population-specific in the Zel, and
haplotype H
2
only occurred in Lori-Bakhtiari breed. The existenc
e of two common
Haplotypes (H
1
and H
3
) in the animals suggest that the two Iranian breed
s from strikingly
different geographical regions, may share a common
ancestry, and these haplotypes could
be the origin haplotypes while the population speci
fic haplotypes developed later.
Keywords:
Genetic diversity, Haplogroups, Mitochondrial genom
e, Phylogenetic study,
Sheep evolution.
