最近又有人遇到mega构建进化树时报错,所以分享一下这个经验给大家。
Oops!MEGA has encountered an error and cannot continue with this analysis:Some pairwise distances could not be estimated.For example,between sequences 23 and 11.
我们在用MEGA构建进化树的时候会遇见,报错信息:
Oops!MEGA has encountered an error and cannot continue with this analysis:Some pairwise distances could not be estimated.For example,between sequences 23 and 11.
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这是因为你的序列差异太大,无法构建进化树,应当将序列差异较大的gap给删除掉,再进行进化树分析,如下图所示:
当然手动删除可能比较主观,也有一个软件gblocks可以提取序列的保守区域;
在线网址:http://molevol.cmima.csic.es/castresana/Gblocks_server.html