Is there aneuploid evolution?

为了在DNA水平上鉴定在四叶草(2n=2x=18)和百合(2n=2x=16)种间杂种中观察到的一条额外染色体，利用Fosid和cDNA克隆序列开发了169个SSR标记，并在四叶草和诸葛菜的F2群体中构建了部分连锁图谱。接下来，进行了Fosid-FISH分析，以筛选来自额外染色体的Fosid克隆，但所测试的19个克隆的FISH信号没有在额外染色体上形成。此外，包括在南亚采集的其他7个种的系统发育分析表明，贝氏锥虫在物种形成过程中丢失了额外的染色体。

To identify an extra chromosome observed in interspecific hybrid between Torenia fournieri (2n=2x=18) and Torenia baillonii (2n=2x=16) at DNA level, 169 SSR markers were developed using fosmid and cDNA clone sequences and a partial linkage map was constructed in F_2 population of T. fournieri and T. violacea. Next, fosmid-FISH analysis has been conducted to screen fosmid clones derived from the extra chromosome, but the FISH signals of 19 clones tested did not formed on the extra chromosome. In addition, phylogenic analysis including other 7 Torenia species collected in south Asia suggests a hypothesis that T. baillonii lost the extra chromosome during the speciation.