Abstract: Objective To study ApoB gene genetic polymorphism of Han nationality and Mongolian nationality in midwest area of Inner Mongolia. Methods Some unrelated individuals of Han nationality and Mongolian nationality in midwest area of Inner Mongolia were selected. Polymerase chain reaction-restriction fragment length polymorphism technology was used to check the presence of XbaⅠ（X+） and EcoRⅠ（E-） sites of rare alleles. The genotype frequency, allelic frequency and population genetics parameters were calculated. Results The frequencies of XbaⅠ（X+） and EcoRⅠ（E-） rare alleles were 2% and 4.6% in Han population. There was no XbaⅠ（X+） or EcoRⅠ（E-） rare alleles found in Mongolian nationality. Conclusion The allelic frequencies of ApoB gene XbaⅠ and EcoRⅠ sites are very different in different races. These sites may be used in identification of ethnicity.

Key words: forensic genetics, polymorphism, genetic, apolipoproteins B, Inner Mongolia, Han nationality, Mongolian nationality