Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, Korea.
Genes (Basel). 2021 Feb 8;12(2):240. doi: 10.3390/genes12020240.
The major histocompatibility complex (MHC) is a highly polymorphic gene region that regulates cellular communication in all specific immune responses. In this study, we investigated 11 microsatellite (MS) markers in the MHC- region of chicken populations from four countries: Sri Lanka, Bangladesh, South Korea, and Nigeria. The MS markers were divided into two sets. Set 1 included five novel MS markers, which we assessed using 192 samples from 21 populations. Set 2 included six previously reported markers, which we assessed using 881 samples from 29 populations. The Set 1 MS markers had lower polymorphism (polymorphic information content (PIC) < 0.5) than the Set 2 markers (PIC = 0.4-0.9). In all populations, the LEI0258 marker was the most polymorphic, with a total of 38 alleles (PIC = 0.912, expected heterozygosity (H) = 0.918). Local populations from Sri Lanka, Bangladesh, and Nigeria had higher allele diversity and more haplotypes for Set 2 MS markers than Korean and commercial populations. The Sri Lankan Karuwalagaswewa village population had the highest MHC diversity (mean allele number = 8.17, H = 0.657), whereas the white leghorn population had the lowest (mean allele number = 2.33, H = 0.342). A total of 409 haplotypes (89 shared and 320 unique), with a range of 4 (Rhode Island red) to 46 (Karuwalagaswewa village (TA)), were identified. Among the shared haplotypes, the B21-like haplotype was identified in 15 populations. The genetic relationship observed in a neighbour-joining tree based on the D distance agreed with the breeding histories and geographic separations. The results indicated high MHC diversity in the local chicken populations. The difference in the allelic pattern among populations presumably reflects the effects of different genotypes, environments, geographic variation, and breeding policies in each country. The selection of MHC allele in domestic poultry can vary due to intensification of poultry production. Preserved MHC diversity in local chicken provides a great opportunity for future studies that address the relationships between MHC polymorphisms and differential immune responses.
主要组织相容性复合体（MHC）是一个高度多态的基因区域，调节所有特异性免疫反应中的细胞通讯。在这项研究中，我们调查了来自四个国家（斯里兰卡、孟加拉国、韩国和尼日利亚）的鸡群中的 11 个微卫星（MS）标记。MS 标记分为两组。第一组包括五个新的 MS 标记，我们使用来自 21 个群体的 192 个样本评估了这些标记。第二组包括六个以前报道过的标记，我们使用来自 29 个群体的 881 个样本评估了这些标记。第一组 MS 标记的多态性较低（多态信息含量（PIC）<0.5），而第二组标记的多态性较高（PIC=0.4-0.9）。在所有群体中，LEI0258 标记的多态性最高，共有 38 个等位基因（PIC=0.912，预期杂合度（H）=0.918）。来自斯里兰卡、孟加拉国和尼日利亚的本地群体的第二组 MS 标记的等位基因多样性和单倍型比韩国和商业群体更高。来自斯里兰卡 Karuwalagaswewa 村的群体具有最高的 MHC 多样性（平均等位基因数=8.17，H=0.657），而白来航鸡群体的多样性最低（平均等位基因数=2.33，H=0.342）。总共鉴定出 409 个单倍型（89 个共享和 320 个独特），范围为 4（罗得岛红）到 46（Karuwalagaswewa 村（TA））。在共享的单倍型中，在 15 个群体中鉴定出 B21 样单倍型。基于 D 距离的邻接法构建的遗传关系与育种历史和地理隔离一致。结果表明，本地鸡群具有高度的 MHC 多样性。不同群体之间等位基因模式的差异可能反映了不同基因型、环境、地理变异和每个国家的育种政策的影响。家禽中 MHC 等位基因的选择可能因家禽生产的集约化而有所不同。本地鸡 MHC 多样性的保留为研究 MHC 多态性与免疫反应差异之间的关系提供了很好的机会。
