Vahidi S M F, Faruque M O, Falahati Anbaran M, Afraz F, Mousavi S M, Boettcher P, Joost S, Han J L, Colli L, Periasamy K, Negrini R, Ajmone-Marsan P
Agricultural Biotechnology Research Institute of Iran (ABRII)-North Branch, Rasht, 41635-4115, Iran.
Department of Animal Breeding and Genetics, Bangladesh Agricultural University, Mymensingh, 2202, Bangladesh.
Anim Genet. 2016 Aug;47(4):463-70. doi: 10.1111/age.12429. Epub 2016 Mar 8.
Iranian livestock diversity is still largely unexplored, in spite of the interest in the populations historically reared in this country located near the Fertile Crescent, a major livestock domestication centre. In this investigation, the genetic diversity and differentiation of 10 Iranian indigenous fat-tailed sheep breeds were investigated using 18 microsatellite markers. Iranian breeds were found to host a high level of diversity. This conclusion is substantiated by the large number of alleles observed across loci (average 13.83, range 7-22) and by the high within-breed expected heterozygosity (average 0.75, range 0.72-0.76). Iranian sheep have a low level of genetic differentiation, as indicated by the analysis of molecular variance, which allocated a very small proportion (1.67%) of total variation to the between-population component, and by the small fixation index (FST = 0.02). Both Bayesian clustering and principal coordinates analysis revealed the absence of a detectable genetic structure. Also, no isolation by distance was observed through comparison of genetic and geographical distances. In spite of high within-breed variation, signatures of inbreeding were detected by the FIS indices, which were positive in all and statistically significant in three breeds. Possible factors explaining the patterns observed, such as considerable gene flow and inbreeding probably due to anthropogenic activities in the light of population management and conservation programmes, are discussed.
尽管位于主要家畜驯化中心新月沃地附近的伊朗，其历史上饲养的家畜种群备受关注，但伊朗家畜的多样性在很大程度上仍未得到充分探索。在本研究中，利用18个微卫星标记对10个伊朗本土肥尾羊品种的遗传多样性和分化情况进行了调查。结果发现伊朗品种具有高度的多样性。这一结论得到了各基因座上观察到的大量等位基因（平均13.83个，范围7 - 22个）以及品种内较高的预期杂合度（平均0.75，范围0.72 - 0.76）的证实。分子方差分析表明，伊朗绵羊的遗传分化水平较低，该分析将总变异中非常小的比例（1.67%）分配给了群体间成分，且固定指数较小（FST = 0.02）。贝叶斯聚类分析和主坐标分析均表明不存在可检测到的遗传结构。此外，通过比较遗传距离和地理距离，未观察到隔离距离现象。尽管品种内变异较高，但通过FIS指数检测到了近交特征，所有品种的FIS指数均为正值，其中三个品种具有统计学意义。本文还讨论了可能解释所观察到模式的因素，如鉴于种群管理和保护计划，人为活动可能导致的大量基因流动和近交。
