Estimation of microsatellite mutation rates in Drosophila Melanogaster

Microsatellite mutations were studied in a set of 175 mutation accumulation lines, all of them independently derived from a completely homozygous popu lation of Drosophila melanogaster and maintained under strong inbreeding du ring 80 generations. We assayed 28 microsatellites and detected two mutatio ns, One mutation consisted of a single addition of it dinucleotide repeat a nd the other was a deletion of five trinucleotide repeats. The average muta tion rate was 5.1 x 10(-6), in full agreement with previous estimates from two different sets of mutation accumulation lines.