Determination of microsatellite DNA mutation rates, mutation models and mutation bias in four main felidae lineages (European wild cat, Felis silvestris; ocelot, Leopardus pardalis; puma, Puma concolor; jaguar, Panthera onca)

We analyzed for 12 nuclear DNA microsatellites in 4 wild cat species (Europeanwild cat, ocelot, puma, and jaguar) representing four different phylogenetics felidlineages. The objective of our study, using these species and molecular markers, was toobtain more data about the molecular evolution of microsatellites. The main findings ofthis study are: 1- From the measurements of diverse genetics variables and statistics inthe four species, we determined that the ocelot showed the highest number of alleles, number of repeats, allele range and levels of heterozygosity. However, no significantdifferences were observed among the average microsatellite mutation rates observed inthe four species of felids studied. 2- We estimated two independent average mutationrates (3.116 x 10-5 and 5.353 x 10-5) using two different phylogenetics strategies.However, there was no significant difference between these two estimates. 3- We foundthe observed mutation model to be basically a uni-step mutation model or a two-phasemutation model. The four felid species showed an average stepwise mutation model for92-94 % of the uni-step mutations. 4- The regression models we applied among differentgenetic diversity statistics, samples sizes and other variables showed: a- the allele rangewas clearly more correlated with the allele number at the microsatellites studied than tothe allele dispersion, b- There was no clear relationship between the microsatellite sizesand the degree of genetic variability that these microsatellites showed in the four felidsstudied, c- There was no evidence of a positive relationship between more mutations andan increase in microsatellite size in our study. This finding was independent of themicrosatellite size being measured by its total size or by the number of repetitiontandems, d- There was no relationship between the allele expansion rate and the level ofgenetic diversity determined in these microsatellites, e- With the exception of the ocelot,the other three our analysis of felid species individually, as well as the overall analysis ofthe four species together, did not detect an average winning or losing of repeat tandemnumbers regarding the employed microsatellites cloned in the domestic cat; therefore,ascertainment bias was not found in this study, f- Sample size played an important role indetermining the accurate levels of gene diversity in the four felid species studied. Wedetermined the number of alleles per locus to be around 42-50 %, the heterozygosity tobe around 23-28 % and the statistic for multiple mutation models to be around 10-13 %,per sample size. The number of alleles per locus, was the statistic most influenced bysample size whereas was the statistic least influenced by the sample size. 5- There wasa significant fraction of microsatellites affected by mutation bias by using the Garza etal., (1995)'s procedure and 6 - In contrast to many authors who have suggested thatmicrosatellite markers are not useful as phylogenetics tools, we document that, withcertain restrictions and considerations, some microsatellite sets can be helpful inphylogenetics tasks, at least, in the felids.