Neel J V, Baier L, Hanash S, Erickson R P
J Hered. 1985 Sep-Oct;76(5):314-20.
Three different inbred strains of mice have been crossed with a lethal albino line (cch/c3H) and the liver polypeptides of the parents and offspring examined by two-dimensional polyacrylamide gel electrophoresis for evidences of protein polymorphisms, different alleles of which have gone to fixation in different strains. In the battery of polypeptides considered most favorable for scoring, 3.3 +/- 1.6 percent of the battery exhibited paired variants and 1.6 +/- 1.2 percent, unpaired. An adjustment for the fact the same allele of a biallelic polymorphism may go to fixation in two inbred lines of common ancestry leads to the suggestion that in the stock from which these inbred lines were ultimately derived, there were some 11.0 percent paired and 5.3 percent unpaired polymorphisms in the average mouse. This is about half the frequency of polymorphisms observed in wild European Mus musculus musculus and Mus musculus domesticus with one-dimensional electrophoresis of blood plasma and erythrocyte proteins. Three explanations were considered for the lower estimated frequency for liver protein polymorphisms: the difference is real, the apparent difference is due to the lower resolving power of two-dimensional gels, or the mouse strains from which the present inbred lines were drawn had already, lost through inbreeding, a considerable amount of their genetic variation before the inbreeding leading to the present strains commenced.
三种不同的近交系小鼠与一个致死性白化品系（cch/c3H）进行了杂交，并通过二维聚丙烯酰胺凝胶电泳对亲本和后代的肝脏多肽进行了检测，以寻找蛋白质多态性的证据，其中不同的等位基因在不同品系中已固定下来。在被认为最有利于计分的一组多肽中，该组多肽的3.3±1.6%表现出成对变异，1.6±1.2%表现出不成对变异。由于双等位基因多态性的相同等位基因可能在两个具有共同祖先的近交系中固定下来，对此进行调整后表明，在这些近交系最终所源自的种群中，平均每只小鼠约有11.0%的成对多态性和5.3%的不成对多态性。这大约是在对欧洲野生小家鼠和家鼠的血浆和红细胞蛋白进行一维电泳时所观察到的多态性频率的一半。对于肝脏蛋白质多态性估计频率较低的情况，考虑了三种解释：差异是真实存在的；明显的差异是由于二维凝胶的分辨能力较低；或者是在导致当前品系的近交开始之前，当前近交系所源自的小鼠品系已经通过近亲繁殖丧失了大量的遗传变异。
