Queensland Statistical Genetics Laboratory, Queensland Institute of Medical Research, 300 Herston Road, Brisbane, Queensland 4006, Australia.
Nat Rev Genet. 2010 Nov;11(11):800-5. doi: 10.1038/nrg2865. Epub 2010 Sep 28.
Identity by descent (IBD) is a fundamental concept in genetics and refers to alleles that are descended from a common ancestor in a base population. Identity by state (IBS) simply refers to alleles that are the same, irrespective of whether they are inherited from a recent ancestor. In modern applications, IBD relationships are estimated from genetic markers in individuals without any known relationship. This can lead to erroneous inference because a consistent base population is not used. We argue that the purpose of most IBD calculations is to predict IBS at unobserved loci. Recognizing this aim leads to better methods to estimating IBD with benefits in mapping genes, estimating genetic variance and predicting inbreeding depression.
遗传同源（IBD）是遗传学中的一个基本概念，指的是来自基础群体中共同祖先的等位基因。遗传同型（IBS）则简单地指的是相同的等位基因，而不管它们是否来自最近的祖先。在现代应用中，IBD 关系是根据个体中没有任何已知关系的遗传标记来估计的。这可能会导致错误的推断，因为没有使用一致的基础群体。我们认为，大多数 IBD 计算的目的是预测未观察到的位点的 IBS。认识到这一目标，就可以采用更好的方法来估计 IBD，从而在基因定位、遗传方差估计和预测近交衰退方面带来好处。
