In this study, genetic characteristics of four tilapia strains including NOVIT4, 13th GIFT generation, China and Philippine were investigated by analysis the genotype at 6 microsatellite loci. It was found that all loci showed high polymorphism with 51 identified alleles, in which GM139 and UNH995 loci were the highest polymorphism with the appearance of 14 and 11 alleles, respectively. | Genetic characteristics in four farmed tilapia Oreochromis niloticus populations evaluated by microsatellite markers