Abstract: Objective To observe and analyze the mutation phenomenon of 17 STR loci of PowerPlex?誖18D Kit in paternity test of Yunnan population. Methods The DNA was extracted by Chelex-100 method. The PowerPlex?誖18D Kit was used to test 1 483 cases and their conclusions of paternity tests were verified. Results In the 1 483 cases, 1 047 were parental triplet and 436 were uniparental diad. A total of 2 530 times of meiosis was observed. One STR locus mutation was observed in 24 cases. And 11 mutation loci were found in the 17 STR loci. Conclusion STR loci mutation is a common phenomenon. We should collect the data of STR loci mutation, choose other good polymorphism, low mutation rate of genetic markers, to ensure that the results are accurate and reliable.

Key words: forensic genetics, mutation, parent-child relations, Yunnan