ABSTRACT
OBJECTIVE@#To study the suspected autosomal STR loci mutation cases.@*METHODS@#A total of 227 suspected autosomal STR loci mutation cases were selected from Center of Forensic Sciences, Beijing Genomics Institute. The allelic mutation cases were screened and the number of mutation of each STR loci was statistically analyzed. The CPI value was calculated in order to study the characteristics and rules of the mutations.@*RESULTS@#In the 227 suspected mutation cases, 3 cases were excluded paternity, and 228 mutations were observed at 18 STR loci in the rest of the cases. The average number of STR mutation loci was 1-2. The maximum of mutation step was 4. After using 20A amplification kit, the CPI values in 3 non-parentage cases were all less than 10(4). After using 20A and 10G amplification kits, the CPI values were all larger than 10(4) in all standard parents-child triplet cases and in 99.45% of diad cases.@*CONCLUSION@#The allelic mutation of STR loci is relatively common in forensic cases. By increasing the number of the required STR loci and supplementing the samples of the triplet, the identification errors could be decreased to a great extent when suspected autosomal STR loci mutation occurs.
Subject(s)
Female , Humans , Male , DNA Fingerprinting , Forensic Medicine , Gene Frequency , Genetic Loci , Microsatellite Repeats , Mutation , Paternity , Reagent Kits, Diagnostic , Retrospective StudiesABSTRACT
OBJECT@#To study sequence polymorphism of mtDNA control region in Chinese Qinghai Tibetan group and Han population.@*METHODS@#Venous blood samples from 69 unrelated Qinghai Tibetans and Han individuals were collected and their mtDNA control region sequences were analyzed. Polymorphism indicators were calculated. The genetic distances based on Fst and Rst among eleven groups from different districts include the Qinghai Tibetan and Han population were elucidated using Nei's method. Phylogenetic tree was constructed.@*RESULTS@#There were 56 polymorphic loci and 59 loci found in the mtDNA control region of Tibetan group and Han population, respectively. It was indicated by the Rst distance that there was a far distance between Qinghai Tibetan and the other populations (P<0.05), and the distance was much closer between Qinghai Han and Xi'an Han, Mongolian, Changsha Han populations (P>0.05).@*CONCLUSION@#There is unique genetic polymorphism of mtDNA control region both in Qinghai Tibetan and Han population. These findings may be useful in forensic identification, population genetic and migration studies.