Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover (Foundation), Germany.
J Anim Breed Genet. 2011 Jun;128(3):219-29. doi: 10.1111/j.1439-0388.2010.00901.x. Epub 2011 Jan 12.
Results from radiographic screening for canine hip dysplasia (CHD) and elbow dysplasia (CED) of 48 367 German shepherd dogs born in 2001-07 were used for the population genetic analyses. Available information included CHD scores for 47 730 dogs, CED scores for 28 011 dogs and detailed veterinary diagnoses of primary ED lesions for a subsample of 18 899 dogs. Quasi-continuous traits were CHD, CED and cases of CED without radiographically visible primary lesion (CED-ARTH). Binary coding was used for fragmented medial coronoid process of the ulna (FCP), borderline findings and mild to severe signs of dysplasia in hip and elbow joints. Genetic parameters were estimated in univariate threshold and multivariate linear and mixed linear-threshold models using Gibbs sampling. Correlations between univariately predicted breeding values (BV) indicated genetic differences between borderline and affected disease status for both CHD (r(BV) = 0.5) and CED (r(BV) = 0.3). Multivariate genetic analyses with separate consideration of borderline findings revealed moderate heritabilities of 0.2-0.3 for the quasi-continuous traits with positive additive genetic correlation of 0.3 between CHD and both CED and CED-ARTH. For FCP, heritability of 0.6 and additive genetic correlations of +0.1 to CHD and -0.1 to CED-ARTH were estimated. Results supported the relevant genetic determination of CHD and CED, argued for both diseases against interpretation of borderline findings as healthy and implied genetic heterogeneity of CED. Accordingly, future breeding strategies to reduce the prevalences of CHD and CED in the German shepherd dog should be most efficient when based on BV from multivariate genetic evaluation for CHD, CED-ARTH and FCP with use of the whole scale of categories for classification of CHD and CED.
利用 2001-07 年出生的 48367 只德国牧羊犬的髋关节发育不良（CHD）和肘关节炎（CED）放射筛查结果进行群体遗传学分析。可用信息包括 47730 只犬的 CHD 评分、28011 只犬的 CED 评分以及 18899 只犬的亚样本的原发性 ED 病变的详细兽医诊断。准连续性状包括 CHD、CED 和无放射学可见原发性病变的 CED（CED-ARTH）。采用连续型变量对尺骨冠状突末端不完全骨折（FCP）、边界性发现和髋关节和肘关节的轻至重度发育不良进行二进制编码。使用 Gibbs 抽样在单变量阈值和多变量线性和混合线性-阈值模型中估计遗传参数。单变量预测育种值（BV）之间的相关性表明，CHD（r（BV）=0.5）和 CED（r（BV）=0.3）的边界性发现和受影响疾病状态之间存在遗传差异。在考虑到边界性发现的多变量遗传分析中，准连续性状的遗传力为 0.2-0.3，CHD 与 CED 和 CED-ARTH 之间的加性遗传相关性为 0.3。对于 FCP，遗传力为 0.6，与 CHD 的加性遗传相关性为+0.1，与 CED-ARTH 的加性遗传相关性为-0.1。结果支持 CHD 和 CED 的相关遗传决定，认为这两种疾病都不应将边界性发现解释为健康，并暗示 CED 的遗传异质性。因此，为了降低德国牧羊犬 CHD 和 CED 的流行率，未来的繁殖策略应该基于 CHD、CED-ARTH 和 FCP 的多变量遗传评估的 BV，使用 CHD 和 CED 分类的整个类别范围，最有效。
