Abstract: To investigate the distribution of nine short tandem repeat (STR) loci in the Maonan ethnic group from Guangxi Huanjiang. We collected the sodium citratedblood specimens from 200 healthy unrelated Maonan individuals in Guangxi Huanjiang, and used the Chelex100 method to extracte DNA by using AmpF
STR IdentifilerTM PCR amplification kit and 3100 genetic analyzer. In the study, a total of 37 alleles and 170 genotypes of the nine shorttandem repeat loci were found in 200 specimens. The allele frequency and genotype frequency were 0.0025-0.4600 and 0.0050-0.2300, respectively. The expected distribution of this genotype accords with HardyWeinberg equilibrium(P > 0.05) . The total discrimination power (TDP), total polymorphism information (TPI), cumulative paternity exclusion power(ECP) and average heterozygosity were 0.99999999996, 0.9999985, 0.999996 and 0.8028, respectively. These results demonstrate that these nine STR loci are of high polymorphic value and hereditary stability, and are in accord with Mendel# s law. The data obtained are valuable for rearch in population genetics research, forensic application, and individual identifications.

Key words: Short tandem repeat; Gene frequency; Genetic distance; Maonan Ethnic Group