Feather pecking (FP) is a damaging nonaggressive behavior in laying hens with a heritable component. Its occurrence has been linked to the immune system, the circadian clock, and foraging behavior. Furthermore, dysregulation of miRNA biogenesis, disturbance of the gamma-aminobutyric acid (GABAergic) system, as well as neurodevelopmental deficiencies are currently under debate as factors influencing the propensity for FP behavior. Past studies, which focused on the dissection of the genetic factors involved in FP, relied on single nucleotide polymorphisms (SNPs) and short insertions and deletions < 50 bp (InDels). These variant classes only represent a certain fraction of the genetic variation of an organism. Hence, we reanalyzed whole-genome sequencing data from two experimental populations, which have been divergently selected for FP behavior for over more than 15 generations, performed variant calling for structural variants (SVs) as well as tandem repeats (TRs), and jointly analyzed the data with SNPs and InDels. Genotype imputation and subsequent genome-wide association studies, in combination with expression quantitative trait loci analysis, led to the discovery of multiple variants influencing the GABAergic system. These include a significantly associated TR downstream of the GABA receptor subunit beta-3 (GABRB3) gene, two microRNAs targeting several GABA receptor genes, and dystrophin (DMD), a direct regulator of GABA receptor clustering. Furthermore, we found the transcription factor ETV1 to be associated with the differential expression of 23 genes, which points toward a role of ETV1, together with SMAD4 and KLF14, in the disturbed neurodevelopment of high-feather pecking chickens.

啄羽 (FP) 是具有可遗传成分的蛋鸡的破坏性非攻击性行为。它的发生与免疫系统、生物钟和觅食行为有关。此外，miRNA 生物发生失调、γ-氨基丁酸 (GABAergic) 系统紊乱以及神经发育缺陷目前正在作为影响 FP 行为倾向的因素进行辩论。过去的研究侧重于剖析 FP 中涉及的遗传因素，依赖于单核苷酸多态性 (SNP) 和 < 50 bp (InDels) 的短插入和缺失。这些变异类别仅代表生物体遗传变异的特定部分。因此，我们重新分析了来自两个实验群体的全基因组测序数据，超过 15 代的 FP 行为被不同地选择，对结构变异 (SV) 和串联重复序列 (TR) 进行变异调用，并与 SNP 和 InDel 联合分析数据。基因型插补和随后的全基因组关联研究，结合表达数量性状位点分析，导致发现影响 GABAergic 系统的多个变体。这些包括与 GABA 受体亚基 beta-3 下游显着相关的 TR（导致发现影响 GABAergic 系统的多种变体。这些包括与 GABA 受体亚基 beta-3 下游显着相关的 TR（导致发现影响 GABAergic 系统的多种变体。这些包括与 GABA 受体亚基 beta-3 下游显着相关的 TR（GABRB3 ) 基因，两个靶向多个 GABA 受体基因的 microRNA，以及抗肌萎缩蛋白 ( DMD )，GABA 受体聚集的直接调节剂。此外，我们发现转录因子ETV1与 23 个基因的差异表达有关，这表明ETV1与SMAD4和KLF14在高羽啄食鸡神经发育紊乱中的作用。