Icelandic cattle is believed to have been brought from Norway during the settlement of Iceland around AD 870-930. Previous research on genetic relationships has indicated that Icelandic cattle is most related to northern Nordic indigenous breeds. Using single nucleotide polymorphism genotype data from Icelandic cattle and 29 Northern and Western European cattle breeds, we studied relationships and admixture among these breeds, and assessed population structure in Icelandic cattle. Population structure analysis through principal component analysis, estimation of ancestry, and analysis of patterns of population splitting and mixing revealed that Icelandic cattle are most related to three Finncattle breeds (Eastern, Northern and Western Finncattle), and Swedish Mountain cattle. Icelandic cattle has very low levels of admixture. We observed very limited population structure in Icelandic cattle. The observed structure was due to variable sire contributions. Over 1000 years of almost complete isolation has made Icelandic cattle highly genetically distinct from other cattle breeds.

据信，冰岛的牲畜是在公元870-930年左右的冰岛定居期间从挪威带来的。以前有关遗传关系的研究表明，冰岛牛与北欧北部土著品种关系最密切。使用来自冰岛牛和29个北欧和西欧牛品种的单核苷酸多态性基因型数据，我们研究了这些品种之间的关系和混合，并评估了冰岛牛的种群结构。通过主成分分析，祖先估计以及种群分裂和混合模式分析进行的种群结构分析表明，冰岛牛与三种芬卡特犬（东部，北部和西部芬卡特犬）和瑞典山牛最相关。冰岛牛的掺混物含量非常低。我们观察到冰岛牛的种群结构非常有限。观察到的结构归因于父系贡献的变化。超过1000年的几乎完全隔离已使冰岛牛在遗传上与其他牛品种高度不同。