Detection of Homologous Loci in Sheep and Cattle

Background: The study of the homology of loci between different species has allowed the improvement of specific genetic knowledge and the development of several fundamental concepts. Thanks to this method, Wright discovered the correspondence between a gene and an enzyme (Wright, 1917). In ruminants, this correspondence between loci of different species has been demonstrated for a very long time (Lauvergne, 1979). In fact, the objective of this work was, initially, to use microsatellites recommended for sheep (FAO, 2011) for the amplification of bovine DNA to show that these loci are homologous and, then, to study the genetic diversity and population structure of three groups of each of the two species in Tunisia.
Methods: In this study, we used three microsatellite markers (OarFCB304, OarFCB193 and MAF209) to verify whether they can be amplified in both sheep and cattle. For that, we considered 28 samples of sheep species from 3 different populations and 17 samples of cattle belonging to three breeds. The data obtained were also used to study their genetic diversity and population structure. Result: We have demonstrated the existence of microsatellite regions common to sheep and cattle. Regarding genetic diversity, we observed a heterozygous deficiency in all the studied breeds. Nei’s genetic distances were greater between breeds of cattle than between breeds of sheep.
