Sallam Ahmed M, Gad-Allah Aymen A, Albetar Essam M
Animal and Poultry Division, Desert Research Center, 1st Mathaf El-Mataryia, 11735, Cairo, Egypt.
Department of Wool Technology and Production, Desert Research Center, 1st Mathaf El-Mataryia, 11735, Cairo, Egypt.
Arch Anim Breed. 2022 Aug 5;65(3):293-300. doi: 10.5194/aab-65-293-2022. eCollection 2022.
The objective of this study was to investigate the genetic polymorphisms in the keratin-associated protein () gene in Barki ( ), Rahmani ( ) and Ossimi ( ) as the three major sheep breeds in Egypt. Subsequently, the detected variants were correlated with important wool traits. The traits included greasy fleece weight (GFW, g), staple length (SL, cm), prickle factor (PF, %), medullated fiber (MF, %), fiber diameter (FD, m), crimp percentage (CR, %) and the standard deviation of FD (SD , m), as well as the subjectively assessed traits of kemp score (KS), handle grade (HG), greasy color grade (GCG), bulk grade (BG), luster grade (LG) and staple structure (SST). Animals were genotyped by polymerase chain reaction (PCR) - single strand conformation polymorphism (SSCP). Five SSCP banding patterns representing three different nucleotide variants (A, B and C) were detected. DNA sequencing confirmed three single nucleotide polymorphisms (SNPs). Animal age significantly affected GFW ( ), SD ( ), SL ( ), CR ( ), KS ( ), LG ( ) and SST ( ). Likewise, the breed had a significant effect on all studied traits except HG and BG, which was not significant. Results showed significant associations between the variants and CR ( ), SL ( ), KS ( ) and GCG ( ). Interestingly, animals with BB genotypes tended to produce more wool yield ( g) with high SL ( cm), CR ( %) and KS ( ). Results of this study strongly recommend the gene as a candidate gene for wool production traits in Egyptian sheep, with new useful insights into the visually assessed wool traits. The identified genetic markers may be incorporated into breeding strategies and genetic improvement programs of wool traits in Egyptian sheep.
本研究的目的是调查埃及三大主要绵羊品种巴尔基羊（Barki）、拉赫曼尼羊（Rahmani）和奥西米羊（Ossimi）中角蛋白相关蛋白（）基因的遗传多态性。随后，将检测到的变异与重要的羊毛性状进行关联分析。这些性状包括毛丛重量（GFW，克）、毛纤维长度（SL，厘米）、刺痒因子（PF，%）、有髓纤维（MF，%）、纤维直径（FD，微米）、卷曲率（CR，%）以及FD的标准差（SD ，微米），还有主观评估的死毛评分（KS）、手感等级（HG）、油脂色泽等级（GCG）、蓬松度等级（BG）、光泽度等级（LG）和毛纤维结构（SST）。通过聚合酶链反应（PCR）-单链构象多态性（SSCP）对动物进行基因分型。检测到代表三种不同核苷酸变异（A、B和C）的五种SSCP条带模式。DNA测序证实了三个单核苷酸多态性（SNP）。动物年龄对GFW（）、SD （）、SL（）、CR（）、KS（）、LG（）和SST（）有显著影响。同样，品种对除HG和BG外的所有研究性状都有显著影响，HG和BG不显著。结果表明，变异与CR（）、SL（）、KS（）和GCG（）之间存在显著关联。有趣的是，基因型为BB的动物往往能产出更多羊毛（ 克），且SL（ 厘米）、CR（ %）和KS较高（）。本研究结果强烈推荐将该基因作为埃及绵羊羊毛生产性状的候选基因，为视觉评估的羊毛性状提供了新的有用见解。所鉴定的遗传标记可纳入埃及绵羊羊毛性状的育种策略和遗传改良计划中。
