Arnott Elizabeth R, Peek Lincoln, Early Jonathan B, Pan Annie Y H, Haase Bianca, Chew Tracy, McGreevy Paul D, Wade Claire M
Faculty of Veterinary Science, University of Sydney, Camperdown, NSW 2006 Australia.
Canine Genet Epidemiol. 2015 May 7;2:6. doi: 10.1186/s40575-015-0017-6. eCollection 2015.
Working dog handlers and breeders have strong opinions on characteristics that are desirable in the breeds that they use to handle stock. Most of these characteristics are related to conformation or behaviour. This study explored whether the genetics underlying desirable working behaviour traits might be identified by selective sweep analysis; a method that identifies long regions of strong homozygosity combined with allelic divergence from a comparison group. For this analysis, we compared genomic haplotype architecture in two breeds derived from common founder stock but subjected to divergent selective pressures. The breeds studied were the Australian Kelpie, which is registered with the Australian National Kennel Council, and the Australian Working Kelpie, which is registered with the Working Kelpie Council.
A selective sweep spanning 3 megabases on chromosome 3 was identified in the Australian Working Kelpie. This region is the location of genes related to fear-memory formation and pain perception. Selective sweep loci of similar magnitude were observed in the Australian Kelpie. On chromosome 8 is a locus which may be related to behavioural excitability and on chromosome 30 is a smaller locus which most likely is related to morphology.
Active working stock dogs of the Australian Working Kelpie breed have been bred primarily for gene loci influencing pain perception and fear memory formation. By contrast Australian Kelpies are commonly maintained in urban environments where these characteristics are not required and have been affected by selection for conformation and coat colour. The identified loci may aid in the identification of superior working dogs.
工作犬的训导员和繁育者对于他们用于放牧的犬种所期望具备的特征有着强烈的看法。这些特征大多与体型结构或行为有关。本研究探索了是否可以通过选择性清除分析来识别理想工作行为特征背后的基因；该方法可识别出长片段的强纯合性区域，并结合与对照组的等位基因差异。为了进行此分析，我们比较了源自共同祖先种群但受到不同选择压力的两个犬种的基因组单倍型结构。所研究的犬种为在澳大利亚国家犬业理事会注册的澳大利亚卡尔比犬，以及在工作卡尔比犬理事会注册的澳大利亚工作卡尔比犬。
在澳大利亚工作卡尔比犬中，在3号染色体上发现了一个跨度为3兆碱基的选择性清除区域。该区域是与恐惧记忆形成和疼痛感知相关基因的所在位置。在澳大利亚卡尔比犬中也观察到了类似大小的选择性清除位点。在8号染色体上有一个可能与行为兴奋性相关的位点，在30号染色体上有一个较小的位点，极有可能与形态有关。
澳大利亚工作卡尔比犬种的活跃工作犬主要是为影响疼痛感知和恐惧记忆形成的基因位点而培育的。相比之下，澳大利亚卡尔比犬通常饲养在不需要这些特征的城市环境中，并且受到体型结构和毛色选择的影响。所识别出的位点可能有助于识别优秀的工作犬。
