背景:高山美利奴羊是一种适应世界高原寒冷干旱气候的细毛羊新品种。由于其优越的适应性和优良的生产性能,已在西北地区推广。那些与体重有关的特征,羊毛产量,和羊毛纤维特性,这些是高山美利奴羊的经济基本性状,受QTL(定量性状基因座)控制。因此,这些关键经济性状的QTL和遗传标记的鉴定是建立MAS(标记辅助选择)育种程序的关键步骤。
结果:在这项研究中,我们通过使用WGR(全基因组重测序)技术对110个F1代个体进行测序,构建了高山美利奴羊的高密度遗传连锁图谱。鉴定了14,942个SNP(单核苷酸多态性)并进行基因分型。地图跨越2,697.86cM,平均遗传标记间隔为1.44cM。共有1871个高质量的SNP标记分布在27个连锁群体中,每个LG(联动组)平均有69个标记。其中,LG2的最小遗传距离为19.62cM,LG19的最大遗传距离为237.19cM。LGs中标记之间的平均遗传距离为0.24cM(LG2)至3.57cM(LG17)。LGs中的标记密度范围为LG14(39个标记)至LG1(150个标记)。
结论:我们构建的高山美利奴羊的第一个遗传图谱包括14,942个SNP,而46个QTL与体重相关,羊毛产量和羊毛纤维性状进行了鉴定,为遗传研究和分子标记辅助育种奠定基础。值得注意的是,LG4和LG8上有重叠性状的QTL区间,为多性状共育提供了潜在的机会,并为超细和肉质高山美利奴羊的选育提供了进一步的理论支持。
BACKGROUND: The Alpine Merino is a new breed of fine-wool sheep adapted to the cold and arid climate of the plateau in the world. It has been popularized in Northwest China due to its superior adaptability as well as excellent production performance. Those traits related to body weight, wool yield, and wool fiber characteristics, which are economically essential traits in Alpine Merino sheep, are controlled by QTL (Quantitative Trait Loci). Therefore, the identification of QTL and genetic markers for these key economic traits is a critical step in establishing a MAS (Marker-Assisted Selection) breeding program.
RESULTS: In this study, we constructed the high-density genetic linkage map of Alpine Merino sheep by sequencing 110 F1 generation individuals using WGR (Whole Genome Resequencing) technology. 14,942 SNPs (Single Nucleotide Polymorphism) were identified and genotyped. The map spanned 2,697.86 cM, with an average genetic marker interval of 1.44 cM. A total of 1,871 high-quality SNP markers were distributed across 27 linkage groups, with an average of 69 markers per LG (Linkage Group). Among them, the smallest genetic distance is 19.62 cM for LG2, while the largest is 237.19 cM for LG19. The average genetic distance between markers in LGs ranged from 0.24 cM (LG2) to 3.57 cM (LG17). The marker density in the LGs ranged from LG14 (39 markers) to LG1 (150 markers).
CONCLUSIONS: The first genetic map of Alpine Merino sheep we constructed included 14,942 SNPs, while 46 QTLs associated with body weight, wool yield and wool fiber traits were identified, laying the foundation for genetic studies and molecular marker-assisted breeding. Notably, there were QTL intervals for overlapping traits on LG4 and LG8, providing potential opportunities for multi-trait co-breeding and further theoretical support for selection and breeding of ultra-fine and meaty Alpine Merino sheep.