Yosida T H
Chromosoma. 1977 Apr 20;60(4):391-8. doi: 10.1007/BF00292861.
Frequencies of the acrocentric and subtelocentric polymorphism in pairs no. 1, 9 and 13 chromosomes have been examined in 358 black rats. Rattus rattus, distributed over several countries of Asia, Austrailia and United States. The black rats are divided into three geographical types by the different chromosome numbers, such as Asian (2n=42), Ceylon (2n=40) and Oceanian types (2n=38). Pairs no. 13 polymorphism was found widely in these all types, but the pair no. 1 and 9 polymorphisms were found in only Asian type black rats. In the Asian type rats, however, those distributed in northern India and Pakistan showed always the subtelocentric pairs no. 1 and 9 like as those in Ceylon and Oceanien type rats have developed in India or Pakistan from the Asian type. The present study also suggests that inversion of the pair no. 13 could have occurred in earlier period than those of the pairs no. 1 and 9.
在358只黑鼠中检查了1号、9号和13号染色体对中近端着丝粒和亚端着丝粒多态性的频率。黑家鼠分布于亚洲、澳大利亚和美国的几个国家。根据不同的染色体数目，黑鼠分为三种地理类型，如亚洲型（2n = 42）、锡兰型（2n = 40）和大洋洲型（2n = 38）。13号染色体对的多态性在所有这些类型中都广泛存在，但1号和9号染色体对的多态性仅在亚洲型黑鼠中发现。然而，在亚洲型大鼠中，分布在印度北部和巴基斯坦的那些大鼠总是表现出亚端着丝粒的1号和9号染色体对，就像锡兰型和大洋洲型大鼠在印度或巴基斯坦从亚洲型进化而来一样。本研究还表明，13号染色体对的倒位可能比1号和9号染色体对的倒位发生得更早。
