Formal Comment to Pettengill: The Time to Most Recent Common Ancestor Does Not (Usually) Approximate the Date of Divergence.
Formal Comment to Pettengill: The Time to Most Recent Common Ancestor Does Not (Usually) Approximate the Date of Divergence.
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DOI：
10.1371/journal.pone.0134435
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Didelot X
中科院分区：
文献类型：
--
作者：
Achtman M;Zhou Z;Didelot X
2013年，Zhou等人得出结论，肠道沙门氏菌血清型Agona代表了最近祖先的遗传单态性谱系，其最近的共同祖先存在于1932年或更早。Agona由三个具有最小突变多样性的谱系组成：自1932年Agona进化以来，只有846个单核苷酸多态性（SNP）在非重复的核心基因组中积累，随后在20世纪60年代经历了一次重大的人口扩张。这些结论现在已经被Pettengill批评，他声称用于确定Agona日期的进化模型可能不合适，日期估计不准确，Agona出现的年龄应该有一个上限，反映了它与外群Soerenga血清型的分歧。我们对这些说法提出异议。首先，佩滕吉尔对阿戈纳的分析在技术上是不合理的。其次，如果外群与Agona密切相关，则与外群的分歧上限才有意义，但Agona的近亲尚未确定。第三，不可能可靠地确定Agona和Soerenga之间分歧的时间。我们的结论是，佩滕吉尔的批评是一个茶壶风暴。
In 2013 Zhou et al. concluded that Salmonella enterica serovar Agona represents a genetically monomorphic lineage of recent ancestry, whose most recent common ancestor existed in 1932, or earlier. The Abstract stated ‘Agona consists of three lineages with minimal mutational diversity: only 846 single nucleotide polymorphisms (SNPs) have accumulated in the non-repetitive, core genome since Agona evolved in 1932 and subsequently underwent a major population expansion in the 1960s.’ These conclusions have now been criticized by Pettengill, who claims that the evolutionary models used to date Agona may not have been appropriate, the dating estimates were inaccurate, and the age of emergence of Agona should have been qualified by an upper limit reflecting the date of its divergence from an outgroup, serovar Soerenga. We dispute these claims. Firstly, Pettengill’s analysis of Agona is not justifiable on technical grounds. Secondly, an upper limit for divergence from an outgroup would only be meaningful if the outgroup were closely related to Agona, but close relatives of Agona are yet to be identified. Thirdly, it is not possible to reliably date the time of divergence between Agona and Soerenga. We conclude that Pettengill’s criticism is comparable to a tempest in a teapot.