Pérez-Montarelo Dafne, Rodríguez M Carmen, Fernández Almudena, Benítez Rita, García Fabián, Silió Luis, Fernández Ana I
Mejora Genética Animal, Instituto Nacional de Tecnología Agraria y Alimentaria, Ctra. de la Coruña km. 7.5, 28040, Madrid, Spain.
J Appl Genet. 2015 Nov;56(4):525-533. doi: 10.1007/s13353-015-0284-7. Epub 2015 Apr 25.
The analysis of structural genetic variability in candidate genes can make it possible to analyse the selection footprint and deepen the understanding of the genetic basis of complex traits. The leptin (LEP) and its receptor (LEPR) porcine genes are involved in food intake and energy homeostasis, and polymorphisms associated to growth and fatness traits have been detected in both genes. The main objective of this study was to explore the genetic variability of the most polymorphic regions of both genes in a variety of pig populations and wild boars from diverse European and Asian origins. In total, 54 animals were included in the analyses, with a remarkable sampling of Spanish wild boars and Iberian pigs. The sequencing allowed the identification of 69 and 26 polymorphisms in LEP and LEPR genes, respectively. Neighbour-joining trees built for the 69 haplotypes identified in the LEP and the 24 haplotypes detected in the LEPR showed the known genetic divergence between European and Asian pig breeds. A high variability of the LEP was detected in the different analysed populations providing new data for the existence of two domestication centres in Asia. In comparison to the LEP gene, the LEPR showed a lower variability, especially in the Iberian breed that showed no variability. Moreover, results of the Hudson-Kreitman-Aguadé neutrality test support a possible selection event of the LEPR gene region in this breed, potentially related with its leptin resistance pattern and good adaptation to a traditional extensive production system with strong seasonal changes of feeding resources.
对候选基因结构遗传变异性的分析能够分析选择印记，并加深对复杂性状遗传基础的理解。猪的瘦素（LEP）及其受体（LEPR）基因参与食物摄入和能量稳态，并且在这两个基因中均检测到了与生长和脂肪性状相关的多态性。本研究的主要目的是探索来自欧洲和亚洲不同地区的各种猪群和野猪中这两个基因最具多态性区域的遗传变异性。分析总共纳入了54只动物，其中西班牙野猪和伊比利亚猪的样本量可观。测序分别在LEP和LEPR基因中鉴定出69个和26个多态性。为LEP中鉴定出的69个单倍型和LEPR中检测到的24个单倍型构建的邻接树显示了欧洲和亚洲猪品种之间已知的遗传差异。在不同分析群体中检测到LEP具有高度变异性，为亚洲存在两个驯化中心提供了新数据。与LEP基因相比，LEPR的变异性较低，尤其是在伊比利亚品种中未表现出变异性。此外，哈德逊-克赖特曼-阿瓜德中性检验的结果支持该品种中LEPR基因区域可能存在选择事件，这可能与其瘦素抵抗模式以及对饲料资源季节性变化强烈的传统粗放生产系统的良好适应性有关。
