Length polymorphism of a microsatellite in human and non human primates

Microsatellites are tandem repeats of short sequences elements (most often CA repeats) interspersed in many genomes and which frequently show multiallele polymorphism. They have proved invaluable for genomic mapping in man and other species and may be used for evolutionary studies provided that the available primers can be used in different species. The dystrophin gene, which shows high sequence conservation between man, rodents and chicken contains such polymorphic CA repeats. Using the oligonucleotides primers developed for testing the polymorphic CA repeat of the 3'untranslated region of the dystrophin gene in man, we achieved the amplification by polymerase chain reaction (PCR) of the analogous region in five non human primates species (Pan troglodytes, Gorilla gorilla, Macaca tonkeana, Macaca fascicularis, Lemur fulvus). All were proved to possess the CA repeat while intraspecies variations of the microsatellite length was observed in chimpanzees, gorillas and tonkean macaques. As it was demonstrated by sequencing, these length variations depend on the number of CA repeats in the microsatellite.