Lei Zhang，Peng Li，Ranran Liu，Maiqing Zheng，Yan Sun，Dan Wu，Yaodong Hu，Jie Wen，Guiping Zhao*

1. Institute of Animal Science，Chinese Academy of Agricultural Sciences，Beijing，P.R. China，

2. Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation，Ministry of Agriculture，P.R. China，Beijing，P.R. China

通訊作者郵箱：zhaoguiping@caas.cn

The Identification of Loci for Immune Traits in Chickens Using a Genome-Wide Association Study

Lei Zhang1，2，Peng Li1，2，Ranran Liu1，2，Maiqing Zheng1，2，Yan Sun1，Dan Wu1，Yaodong Hu1，Jie Wen1，2，Guiping Zhao1，2*

1. Institute of Animal Science，Chinese Academy of Agricultural Sciences，Beijing，P.R. China，

2. Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation，Ministry of Agriculture，P.R. China，Beijing，P.R. China

通訊作者郵箱：zhaoguiping@caas.cn

學(xué)科：畜牧獸醫(yī)

推薦專家：趙桂蘋研究員（中國(guó)農(nóng)業(yè)科學(xué)院北京畜牧獸醫(yī)研究所）

推薦論文：Lei Zhang，Peng Li，Ranran Liu，et al. The Identification of Loci for Immune Traits in Chickens Using a Genome-Wide Association Study ［J］. PLoS One，2015，10（3）： e0117269

·專家點(diǎn)評(píng)·

首次系統(tǒng)、全面地對(duì)雞的6個(gè)免疫形狀指標(biāo)（血清IgG、異嗜細(xì)胞數(shù)、淋巴細(xì)胞數(shù)、異嗜細(xì)胞和淋巴細(xì)胞比率、禽流感抗體滴度和綿羊紅細(xì)胞抗體滴度）進(jìn)行了GWAS分析，篩選出雞16、19號(hào)等染色體免疫相關(guān)區(qū)域的重要候選基因，為深入探究家禽抗病免疫的機(jī)制以及重要基因的功能鑒定奠定了基礎(chǔ)。

本研究新發(fā)現(xiàn)的位于雞16號(hào)染色體狹窄區(qū)段（247kb）的5個(gè)候選基因（CD1b、 IL4I1、GNB2L1、TRIM27和ZNF692），與雞抗病免疫密切相關(guān)。

The genetic improvement of disease resistance in poultry continues to be a challenge. To identify candidate genes and loci responsible for these traits，genome-wide association studies using the chicken 60k high density single nucleotide polymorphism（SNP）array for six immune traits，total serumimmunoglobulin Y（IgY）level，numbers of，and the ratio of heterophils and lymphocytes，and antibody responses against Avian Influenza Virus（AIV）and Sheep Red Blood Cell（SRBC），were performed. RT-qPCR was used to quantify the relative expression of the identified candidate genes. Nine significantly associated SNPs（P ＜ 2.81E-06）and 30 SNPs reaching the suggestively significant level（P ＜ 5.62E-05）were identified. Five of the 10 SNPs that were suggestively associated with the antibody response to SRBC were located within or close to previously reported QTL regions. Fifteen SNPs reached a suggestive significance level for AIV antibody titer and seven were found on the sex chromosome Z. Seven suggestive markers involving five different SNPs were identified for the numbers of heterophils and lymphocytes，and the heterophil/lymphocyte ratio. Nine significant SNPs，all on chromosome 16，were significantly associated with serum total IgY concentration，and the five most significant were located within a narrow region spanning 6.4kb to 253.4kb（P = 1.20E-14 to 5.33E-08）. After testing expression of five candidate genes（IL4I1，CD1b，GNB2L1，TRIM27 and ZNF692）located in this region，changes in IL4I1，CD1b transcripts were consistent with the concentrations of IgY，while abundances of TRIM27 and ZNF692 showed reciprocal changes to those of IgY concentrations. This study has revealed 39 SNPs associated with six immune traits（total serumIgY level，numbers of，and the ratio of heterophils and lymphocytes，and antibody responses against AIV and SRBC）in Beijing-You chickens. The narrow region spanning 247kb on chromosome 16 is an important QTL for serum total IgY concentration. Five candidate genes related to IgY level validated here are novel andmay play critical roles in themodulation of immune responses. Potentially useful candidate SNPs for markerassisted selection for disease resistance are identified. It is highly likely that these candidate genes play roles in various aspects of the immune response in chickens.

責(zé)任編輯：王帥帥