Decrease in repeat number

11 repeat allele

Initiation

11 repeat allele

Dissociation

Newly synthesized strand is different length to template

Rehybridization and misalignment

Newly synthesized strand is different length to template

10 repeat allele after replication

12 repeat allele after replication

10 repeat allele after replication

12 repeat allele after replication

Figure 7.6 Replication slippage and microsatellite mutation. Schematic representation of how after transient dissociation, misalignment may result in gain or loss of a repeat unit in the nascent strand. Redrawn and reprinted by permission from Macmillan Publishers Ltd: Nature Reviews Genetics (Ellegren 2004), copyright 2004; and from Jobling et al. (2004).

Figure 7.6 Replication slippage and microsatellite mutation. Schematic representation of how after transient dissociation, misalignment may result in gain or loss of a repeat unit in the nascent strand. Redrawn and reprinted by permission from Macmillan Publishers Ltd: Nature Reviews Genetics (Ellegren 2004), copyright 2004; and from Jobling et al. (2004).

time, interruptions and deletions lead to degeneracy of microsatellite sequences and 'scrambling' of the sequence, such that 'death' of the microsatellite is seen and the 'life cycle' of the microsatellite can be viewed as complete (Taylor et al. 1999; Buschiazzo and Gemmell 2006). The duration of the life cycle of a microsatellite may represent tens or hundreds of millions of years.

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