Searle J B
Cytogenet Cell Genet. 1986;41(3):154-62. doi: 10.1159/000132220.
Adult male common shrews, both Robertsonian heterozygotes and homozygotes, were collected from Oxford and elsewhere in Britain. In both simple Robertsonian heterozygotes and Robertsonian heterozygotes with monobrachial homology, regular chain configurations were observed at meiosis I; only 1-2% were incomplete such that univalents were observed. On the average, there was one chiasma per chromosome arm among those that displayed Robertsonian variation, including both chain configurations and bivalents. According to one hypothesis, a single chiasma per chromosome arm may facilitate proper disjunction of chain trivalents of simple Robertsonian heterozygotes. Based on metaphase II counts, anaphase I nondisjunction frequency can be estimated as 1.0% per heterozygous individual and 0.7% per heterozygous arm combination.
成年雄性普通鼩鼱，包括罗伯逊易位杂合子和纯合子，采集自牛津及英国其他地区。在简单的罗伯逊易位杂合子和具有单臂同源性的罗伯逊易位杂合子中，在减数分裂I期均观察到规则的链状构型；只有1 - 2%是不完整的，从而观察到单价体。平均而言，在表现出罗伯逊易位变异的个体中，包括链状构型和二价体，每条染色体臂有一个交叉。根据一种假设，每条染色体臂上的单个交叉可能有助于简单罗伯逊易位杂合子的链状三价体正确分离。基于中期II的计数，后期I不分离频率估计为每个杂合个体1.0%，每个杂合臂组合0.7%。
