Many genetic studies, particularly those of recessive traits, have focused on small isolated human populations, such as those on islands. Which are major advantages that isolated populations might provide for the study of recessive traits? Some recessive traits that are rare in most large populations may be relatively common in some small populations. Geneticists are more likely to be able to control mating choices in small populations. Autosomal dominant traits will be more likely to be found in such populations. Small populations likely will experience a high mutation rate and thus produce more genetic variation for study. Inbreeding, which is more common in small populations, will tend to increase the frequency of recessive phenotypes.