Department of Animal Science, University of California, Davis 95616.
USDA-ARS, Avian Disease and Oncology Laboratory, East Lansing, MI 48823.
Poult Sci. 2018 Jun 1;97(6):1872-1880. doi: 10.3382/ps/pey073.
Wingless-2 (wg-2) is an autosomal recessive mutation in chicken that results in an embryonic lethal condition. Affected individuals exhibit a multisystem syndrome characterized by absent wings, truncated legs, and craniofacial, kidney, and feather malformations. Previously, work focused on phenotype description, establishing the autosomal recessive pattern of Mendelian inheritance and placing the mutation on an inbred genetic background to create the congenic line UCD Wingless-2.331. The research described in this paper employed the complementary tools of breeding, genetics, and genomics to map the chromosomal location of the mutation and successively narrow the size of the region for analysis of the causative element. Specifically, the wg-2 mutation was initially mapped to a 7 Mb region of chromosome 12 using an Illumina 3 K SNP array. Subsequent SNP genotyping and exon sequencing combined with analysis from improved genome assemblies narrowed the region of interest to a maximum size of 227 kb. Within this region, 3 validated and 3 predicted candidate genes are found, and these are described. The wg-2 mutation is a valuable resource to contribute to an improved understanding of the developmental pathways involved in chicken and avian limb development as well as serving as a model for human development, as the resulting syndrome shares features with human congenital disorders.
Wingless-2（wg-2）是鸡的常染色体隐性突变，导致胚胎致死。受影响的个体表现出多系统综合征，特征为无翅膀、腿部截断以及颅面、肾脏和羽毛畸形。先前的工作主要集中在表型描述上，确定了孟德尔遗传的常染色体隐性遗传模式，并将突变置于近交遗传背景下，以创建同基因系 UCD Wingless-2.331。本文所述的研究采用了育种、遗传学和基因组学的互补工具，以定位突变的染色体位置，并逐步缩小分析致病因素的区域大小。具体来说，wg-2 突变最初使用 Illumina 3K SNP 阵列映射到 12 号染色体的 7 Mb 区域。随后的 SNP 基因分型和外显子测序结合改进的基因组组装分析将感兴趣的区域缩小到最大 227kb。在这个区域内，发现了 3 个已验证和 3 个预测的候选基因，并对它们进行了描述。wg-2 突变是一个有价值的资源，可以帮助我们更好地理解鸡和禽类肢体发育中涉及的发育途径，并作为人类发育的模型，因为由此产生的综合征与人类先天性疾病具有共同特征。
