Abstract

Cirneco dell’Etna is an old Italian breed of scent hunting dogs. Commonly used genomic measures such as heterozygosity, fixation indexes, and runs of homozygosity can help to improve knowledge about its genetic diversity. This study aimed to: (i) investigate Cirneco’s genomic background, (ii) quantify its genomic inbreeding, and (iii) detect genomic regions differentiating the Cirneco’s two allowed coat colours, self-coloured fawn and tan and white. Canine 230 K SNP BeadChips was used to investigate 24 Cirneco (19 self-coloured fawn, and 5 tan and white) and other 106 dogs from eight phylogenetically and historically related breeds. The genetic distance, ancestry, and relationship among breeds were explored by multidimensional scaling, Reynolds distances, phylogenetic tree, and admixture analysis. The genomic inbreeding (F _ROH) was calculated for each breed. Averaged Wright’s fixation index $\overline{F}$ _ST was used to identify the genes that most differentiated the two groups of Cirneco. All analyses highlighted that Segugio Italiano and Kelb tal Fenek are the closest breeds to Cirneco. Within the breed, tan and white subjects showed a more heterogeneous genetic background and a lower inbreeding in comparison with self-coloured fawn ones, even though more than half of the latter presented a superimposable admixture. The gene that most differentiated these two groups is Microphthalmia-Associated Transcription Factor (MITF), previously associated with white spotting in other breeds. Given the small size of the Cirneco population and its open registry, its management should carefully combine morphological and genealogical evaluations with genetic tools to identify the best breeders while maintaining an acceptable genetic pool.

• Highlights

• The genomic analysis demonstrated that Segugio Italiano and Kelb tal Fenek are genetically related to the Cirneco.

• The MITF gene is responsible for white blazing in Cirneco as in many other dog breeds.

• Genomic tools should be integrated with phenotypic and genealogic evaluations in the management of Italian autochthonous dog breeds to safeguard their welfare and biodiversity.

摘要

Cirneco dell'Etna是古老的意大利猎犬。常用的基因组测量方法（例如杂合性，固定指数和纯合运行）可以帮助提高有关其遗传多样性的知识。这项研究旨在：（i）研究Cirneco的基因组背景，（ii）量化其基因组近交，以及（iii）检测区分Cirneco两种允许的外套颜色的基因组区域，即自着色的小鹿色，棕褐色和白色。犬230 K SNP BeadChip被用于研究24种Cirneco（19种自着色小鹿，5种棕褐色和白色）和其他106种来自8个系统发育和历史相关品种的狗。通过多维标度，雷诺距离，系统树和掺混物分析，探索了品种之间的遗传距离，祖先和关系。基因组近亲繁殖（˚F 计算每个品种的_ROH）。赖特平均注视指数$\overline{F}$ _ST用于鉴定最能区分Cirneco两组的基因。所有分析都强调，Segugio Italiano和Kelb tal Fenek是与Cirneco最接近的品种。与自上色的小鹿相比，在该品种中，棕褐色和白色的对象显示出更多的异质遗传背景和近亲繁殖，尽管后者中有一半以上具有可叠加的混合物。这两组的差异最大的基因是小眼症相关转录因子（MITF），以前与其他品种的白色斑点有关。鉴于Cirneco种群数量少，并且其开放的注册机构，其管理人员应谨慎地将形态学和家谱学评估与遗传工具结合起来，以确定最佳育种者，同时保持可接受的遗传库。

• 强调

• 基因组分析表明，Segugio Italiano和Kelb tal Fenek与Cirneco遗传相关。

• 该MITF基因是负责白色闪耀在购买cirneco在许多其他犬种。

• 在管理意大利本土狗品种时，应将基因组工具与表型和家谱评估相结合，以保护其福利和生物多样性。