What have we figured out about DNA microsatellites?
Microsatellites are extremely valuable markers for the estimation of genetic relatedness (Queller et al. 1993 and many other papers).
The comparative abundance of microsatellites is largely explained at AT/GC content, with genomes rich in either AT or CG having more microsatellites than genomes with balanced content (Tian et al. 2011).
The very high microsatellite content of the D. discoideum genome is not explained by mutation rate; its mutation rate is actually quite low (McConnell 2007).
A large fraction of small insertion mutations in a human database duplicate adjacent sequence, suggesting that slippage during replication, the method by which microsatellites grow, might also explain their origin (Zhu et al. 2000).
The genomes of D. discoideum and its distant relative D. purpureum show very similar patterns of amino acid repeats, largely due to convergent evolution in less important genes in these high AT-content genomes (Sucgang et al. 2011).