The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK.
The Royal Veterinary College, Hawkshead Lane, Hatfield, Hertfordshire, AL9 7TA, UK.
Sci Rep. 2021 Jan 12;11(1):1623. doi: 10.1038/s41598-020-79005-7.
Campylobacter is the leading cause of bacterial foodborne gastroenteritis worldwide. Handling or consumption of contaminated poultry meat is a key risk factor for human campylobacteriosis. One potential control strategy is to select poultry with increased resistance to Campylobacter. We associated high-density genome-wide genotypes (600K single nucleotide polymorphisms) of 3000 commercial broilers with Campylobacter load in their caeca. Trait heritability was modest but significant (h = 0.11 ± 0.03). Results confirmed quantitative trait loci (QTL) on chromosomes 14 and 16 previously identified in inbred chicken lines, and detected two additional QTLs on chromosomes 19 and 26. RNA-Seq analysis of broilers at the extremes of colonisation phenotype identified differentially transcribed genes within the QTL on chromosome 16 and proximal to the major histocompatibility complex (MHC) locus. We identified strong cis-QTLs located within MHC suggesting the presence of cis-acting variation in MHC class I and II and BG genes. Pathway and network analyses implicated cooperative functional pathways and networks in colonisation, including those related to antigen presentation, innate and adaptive immune responses, calcium, and renin-angiotensin signalling. While co-selection for enhanced resistance and other breeding goals is feasible, the frequency of resistance-associated alleles was high in the population studied and non-genetic factors significantly influenced Campylobacter colonisation.
空肠弯曲菌是全球细菌性食源性胃肠炎的主要致病菌。处理或食用受污染的禽肉是人类弯曲菌病的一个关键风险因素。一种潜在的控制策略是选择对空肠弯曲菌具有更高抗性的家禽。我们将 3000 只商业肉鸡的高密度全基因组基因型（600K 个单核苷酸多态性）与盲肠中的空肠弯曲菌负荷相关联。性状遗传力适中但显著（h=0.11±0.03）。结果证实了先前在近交系鸡中发现的 14 号和 16 号染色体上的数量性状基因座（QTL），并在 19 号和 26 号染色体上检测到另外两个 QTL。在定植表型极端的肉鸡的 RNA-Seq 分析中，在 16 号染色体上的 QTL 内和主要组织相容性复合体（MHC）基因座附近鉴定出差异转录基因。我们鉴定出 MHC 内的强顺式 QTL，表明 MHC 类 I 和 II 以及 BG 基因中存在顺式作用变异。途径和网络分析表明，定植涉及协同功能途径和网络，包括与抗原呈递、先天和适应性免疫反应、钙和肾素-血管紧张素信号相关的途径和网络。虽然增强抗性和其他选育目标的共同选择是可行的，但研究人群中抗性相关等位基因的频率很高，非遗传因素对空肠弯曲菌定植有显著影响。
