Molecular Genetic and Genomic Analysis of Mutation Clusters Induced by Ubiquitous Endogenous Mutagenic Processes in Highly Sensitized Yeast Model Systems

在35亿年的时间里，地球上进化出了惊人的生物多样性。自然选择的进化作用于生命形式种群中的遗传变异，因此具有有利遗传特征的个体更有可能生存下来并将其基因传递给下一代。这种遗传变异大多以突变的形式发生，即DNA信息编码内容的改变。突变总是以非常低的“背景”频率发生，但这些突变是如此罕见，以至于它们的起源很难研究，也不能很好地理解。

An amazing diversity of life has evolved on Earth over some 3.5 billion years. Evolution by natural selection acts on the genetic variation within a population of life forms, such that individuals with advantageous genetic traits are more likely to survive and pass on their genes to the next generation. Much of this genetic variation occurs in the form of mutations, which are changes to the information coding content of DNA. Mutations occur all the time at a very low "background" frequency, but these mutations are so rare that their origins are difficult to study and not well understood.