varver: a database of microsatellite variation in vertebrates.

Understanding how genetic variation is maintained within a species is important in ecology, evolution, conservation and population genetics. Tremendous efforts have been made to evaluate the patterns of genetic variation in natural populations of various species. For this purpose, microsatellites have played a major role since the 1990s. Here we describe a comprehensive database, varver (Variation in Vertebrates) that provides complete information regarding microsatellite variation in natural populations of vertebrates. For each species, varver includes basic information of the species, a list of publications reporting the microsatellite variation, and tables of genetic variation within and between populations (heterozygosity and FST ). The geographic location and rough sampling range are also shown for each sampled population. The database should be useful for researchers interested in not only specific species but also comparing multiple species. We discuss the utility of microsatellite data, particularly for meta-analyses that involve multiple microsatellite loci from various species. We show that in such analyses, it is extremely important to correct for biases caused by differences in mutation rate, mainly due to repeat unit and number.