Genomic mutation data

When the model was formulated, the precise mutation frequency of chloro-plast genome mutations was unknown and could only be estimated as being an exceedingly low number, much lower than nuclear mutation frequencies. There are now some data to indicate that the mutation frequency of chloro-plast genes is orders of magnitude higher in certain individual plants than the normal plastid mutation frequency. This is due to a nuclear plastome mutator gene which increases the frequency of chloroplast mutations (18). 

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