Ballan Mohamad, Bovo Samuele, Bertolini Francesca, Schiavo Giuseppina, Schiavitto Michele, Negrini Riccardo, Fontanesi Luca
Division of Animal Sciences, Department of Agricultural and Food Sciences, University of Bologna, Bologna, Italy.
Associazione Nazionale Coniglicoltori Italiani (ANCI), Volturara Appula, Italy.
J Anim Breed Genet. 2023 Nov;140(6):663-678. doi: 10.1111/jbg.12818. Epub 2023 Jul 12.
Following the recent domestication process of the European rabbit (Oryctolagus cuniculus), many different breeds and lines, distinguished primarily by exterior traits such as coat colour, fur structure and body size and shape, have been constituted. In this study, we genotyped, with a high-density single-nucleotide polymorphism panel, a total of 645 rabbits from 10 fancy breeds (Belgian Hare, Champagne d'Argent, Checkered Giant, Coloured Dwarf, Dwarf Lop, Ermine, Giant Grey, Giant White, Rex and Rhinelander) and three meat breeds (Italian White, Italian Spotted and Italian Silver). ADMIXTURE analysis indicated that breeds with similar phenotypic traits (e.g. coat colour and body size) shared common ancestries. Signatures of selection using two haplotype-based approaches (iHS and XP-EHH), combined with the results obtained with other methods previously reported that we applied to the same breeds, we identified a total of 5079 independent genomic regions with some signatures of selection, covering about 1777 Mb of the rabbit genome. These regions consistently encompassed many genes involved in pigmentation processes (ASIP, EDNRA, EDNRB, KIT, KITLG, MITF, OCA2, TYR and TYRP1), coat structure (LIPH) and body size, including two major genes (LCORL and HMGA2) among many others. This study revealed novel genomic regions under signatures of selection and further demonstrated that population structures and signatures of selection, left into the genome of these rabbit breeds, may contribute to understanding the genetic events that led to their constitution and the complex genetic mechanisms determining the broad phenotypic variability present in these untapped rabbit genetic resources.
在欧洲兔（穴兔）近期的驯化过程之后，已经形成了许多不同的品种和品系，主要通过诸如毛色、皮毛结构以及体型和形状等外部特征来区分。在本研究中，我们使用高密度单核苷酸多态性面板对来自10个观赏品种（比利时野兔、香槟银兔、棋盘巨兔、彩色矮兔、矮脚 lop 兔、银貂兔、巨型灰兔、巨型白兔、獭兔和莱茵兰兔）和3个肉用品种（意大利白兔、意大利斑点兔和意大利银兔）的总共645只兔子进行了基因分型。群体结构分析表明，具有相似表型特征（如毛色和体型）的品种共享共同的祖先。使用两种基于单倍型的方法（iHS和XP-EHH）进行选择信号分析，并结合我们先前应用于相同品种的其他方法所获得的结果，我们总共鉴定出5079个具有某些选择信号的独立基因组区域，覆盖了兔基因组约1777 Mb。这些区域一致包含许多参与色素沉着过程的基因（ASIP、EDNRA、EDNRB、KIT、KITLG、MITF、OCA2、TYR和TYRP1）、皮毛结构（LIPH）和体型相关基因，其中包括许多其他基因中的两个主要基因（LCORL和HMGA2）。本研究揭示了处于选择信号下的新基因组区域，并进一步证明了这些兔品种基因组中留下的群体结构和选择信号，可能有助于理解导致它们形成的遗传事件以及决定这些未开发兔遗传资源中广泛表型变异的复杂遗传机制。
