Abstract:
Chicken is a major source of protein for the increasing human population and is useful for research purposes. There are almost 1,600 distinct regional breeds of chicken across the globe, among which a large body of genetic and phenotypic variations has been accumulated due to extensive natural and artificial selection. Moreover, natural selection is a crucial force for animal domestication. Several approaches have been adopted to detect selection signatures in different breeds of chicken using whole genome sequencing (WGS) data including integrated haplotype score (iHS), cross-populated extend haplotype homozygosity test (XP-EHH), fixation index (FST), cross-population composite likelihood ratio (XP-CLR), nucleotide diversity (Pi), and others. In addition, gene enrichment analyses are utilized to determine KEGG pathways and gene ontology (GO) terms related to traits of interest in chicken. Herein, we review different studies that have adopted diverse approaches to detect selection signatures in different breeds of chicken. This review systematically summarizes different findings on selection signatures and related candidate genes in chickens. Future studies could combine different selection signatures approaches to strengthen the quality of the results thereby providing more affirmative inference. This would further aid in deciphering the importance of selection in chicken conservation for the increasing human population.
摘要:
鸡是不断增加的人口的主要蛋白质来源,可用于研究目的。全球有将近1600个不同的地区品种的鸡,其中,由于广泛的自然和人工选择,已经积累了大量的遗传和表型变异。此外,自然选择是动物驯化的重要力量。使用全基因组测序(WGS)数据,包括整合单倍型评分(iHS),已经采用了几种方法来检测不同品种鸡的选择特征。交叉填充扩展单倍型纯合性检验(XP-EHH),固定指数(FST),交叉群体复合似然比(XP-CLR),核苷酸多样性(Pi),和其他人。此外,基因富集分析用于确定与鸡中感兴趣的性状相关的KEGG途径和基因本体论(GO)术语。在这里,我们回顾了不同的研究,这些研究采用了不同的方法来检测不同品种鸡的选择特征。本文系统地总结了鸡的选择特征和相关候选基因的不同发现。未来的研究可以结合不同的选择签名方法来增强结果的质量,从而提供更肯定的推断。这将进一步有助于破译选择在鸡保护中对不断增长的人口的重要性。