Genètica i Millora Animal, Institut de Recerca i Tecnologia Agroalimentàries-Lleida, Lleida, Spain.
J Hered. 2010 May-Jun;101(3):351-9. doi: 10.1093/jhered/esp118. Epub 2009 Dec 23.
The congenic HG.CAST-(D17Mit196-D17Mit190) (HQ17(hg/hg)) mouse strain showed a significant departure on the expected 50%/50% offspring sex ratio in more than 2400 progeny (55.7% females). The entire pedigree file included data from 13 nonoverlapping purebred generations and an F(2) cross with the C57BL/6J inbred strain. Offspring sex ratio data were analyzed on the basis of 40 purebred HQ17(hg)(/hg) sires and 29 F(1) HQ17(hg)(/hg) x B6 sires under a Bayesian Binomial segregation model accounting for 4 different autosomal inheritance models of gene action (i.e., additive, dominance, recessive, and overdominance) and X-linked and Y-linked loci. For each model, the segregation effect was evaluated as a single regression coefficient for all sires or assuming 2 independent regression coefficients accounting for offspring sex ratio departures in purebred and F(1) sires, respectively. The deviance information criterion clearly favored the autosomal dominance model with different regression coefficients for the 2 groups of sires. Under this model, the dominance effect increased the percentage of female offspring by 4.3% (HQ17(hg)(/hg) purebred sires) and 8.2% (F(1) sires) with the highest posterior density regions ranging from 0.5% to 10.6% and from 1.3% to 14.4%, respectively. This article provides significant evidence of genetic determinism for sex ratio distortion in the HQ17(hg)(/hg) strain and develops new analytical tools to perform segregation studies on dichotomous traits.
同源 HG.CAST-(D17Mit196-D17Mit190)(HQ17(hg/hg)) 小鼠品系在超过 2400 只后代中表现出明显偏离预期的 50%/50%后代性别比例（55.7%为雌性）。整个系谱文件包括来自 13 个不重叠的纯系世代和与 C57BL/6J 近交系的 F(2)杂交的数据。根据 40 只纯系 HQ17(hg)(/hg) 雄鼠和 29 只 F(1) HQ17(hg)(/hg)x B6 雄鼠的后代性别比例数据，在贝叶斯二项式分离模型下进行分析，该模型考虑了 4 种不同的常染色体基因作用遗传模型（即加性、显性、隐性和超显性）以及 X 连锁和 Y 连锁基因座。对于每种模型，分离效应均评估为所有雄鼠的单个回归系数，或假设 2 个独立的回归系数，分别用于解释纯系和 F(1)雄鼠后代性别比例偏离。偏差信息准则明显支持具有不同回归系数的常染色体显性模型。在该模型下，显性效应使雌性后代的百分比增加了 4.3%（HQ17(hg)(/hg)纯系雄鼠）和 8.2%（F(1)雄鼠），最高后验密度区介于 0.5%至 10.6%和 1.3%至 14.4%之间。本文为 HQ17(hg)(/hg) 品系中性别比例扭曲的遗传决定因素提供了重要证据，并开发了新的分析工具，用于对二项性状进行分离研究。
