The basidiomycete Schizophyllum commune has the highest level of genetic polymorphism known among living organisms. In a previous study, it was also found to have a moderately high per-generation mutation rate of 2×10⁻⁸, likely contributing to its high polymorphism. However, this rate has been measured only in an experiment on Petri dishes, and it is unclear how it translates to natural populations. Here, we used an experimental design that measures the rate of accumulation of de novo mutations in a linearly growing mycelium. We show that S. commune accumulates mutations at a rate of 1.24×10⁻⁷ substitutions per nucleotide per meter of growth, or ∼2.04×10⁻¹¹ per nucleotide per cell division. In contrast to what has been observed in a number of species with extensive vegetative growth, this rate does not decline in the course of propagation of a mycelium. As a result, even a moderate per-cell-division mutation rate in S. commune can translate into a very high per-generation mutation rate when the number of cell divisions between consecutive meiosis is large.

中文翻译：

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快速积累的高变真菌裂殖酵母菌丝体中的突变。

担子菌Schizophyllum comunune在活生物体中具有最高水平的遗传多态性。在先前的研究中，还发现它具有2×10 ^-8的中等较高的每代突变率，可能有助于其高多态性。但是，该比率仅在皮氏培养皿上的实验中测量过，目前尚不清楚如何将其转化为自然种群。在这里，我们使用了一种实验设计，该设计测量线性增长的菌丝体中从头突变的积累速率。我们表明，S.公社在1.24×10所的速率累积突变^-7每增长米核苷酸取代，或~2.04×10 ^-11每个细胞分裂的核苷酸。与在许多具有广泛营养生长的物种中观察到的相反，该速率在菌丝体繁殖过程中并未下降。其结果是，即使温和每个细胞分裂的突变率S.公社可以转化为一个非常高的每一代的突变率连续时之间减数分裂细胞分裂的数量是很大的。