| Objective: Since mitochondrial DNA (mtDNA) is maternally inherited and exists in a high copy numbers (1000-10000 copies) in each cell in addition to rapidly evolving (5-10 times faster compared to nuclear DNA), the study of the variation in mtDNA is a common task for individual identification and maternal lineage test in forensic science, especially when there are trace and degraded samples in the scean or nuclear DNA is unavailable. mtDNA is composed of coding and non-coding region. Non-Coding region, named as control region (CR) or displacement-loop (D-loop), concludes three hypervariable regions (HV1, 2 and 3). Sequence polymorphisms of the mtDNA are focused on the HV1 and HV2.The D-loop databases about different population were established, which show high polymorphisms. Someone reported that there are no mutations among healthy individuals in coding region. However, recently it is said that there are sequence polymorphism in coding region encompassing position 8389-8865 and cytochrome b gene. Now some population polymorphism datas about HV1 andHV2 are published, but no data about coding region polymorphism in any population and particularly no data about mtDNA in HeBei Han population. To study the polymorphism at the two overlapping fragments of HV1\HV2 and coding region encompassing position 8430-8673 in HeBei Han Population, 100-175 unrelated individuals and ten families were analyzed. Hair shafts that only contain mtDNA are the common biological samples at crime scean. We investigated the length polymorphism at HV3 (CA)n repeats to 20 hair shafts. So we obtained the hereditary data of Chinese HeBei Han Population first time, which is the basis of mtDNA database and it's application in forensic science.Methods: Sodium citrate-blood specimens were ColleCted from 100-175 unrelated healthy individuals. DNA were extracted by salting out method from fresh blood or decomposed blood samples and amplified by polymerase chain reaction (PCR). The PCR products were analyzed by single strand conformation polymorphism (SSCP), following by silver staining. The DNA were extracted by Chelex-100 method from hair shafts and amplified using specific primers. The PCR products were analyzed by PAG vertical electrophoresis, following by silver staining. Samples were typed one by one and gene type distribution was observed. The frequencies of all gene types, gene diversity and random match probability arecalculated. The distributions of all types frequencies were compared to other population data. The sequences were compared to each other by DNASTAR software and Anderson sequence by NCBI BLAST.Results: HV1A: Among the 159 unrelated individuals from HeBei Han Population, 39 types were observed. The gene type frequencies were between 0.006289-0.09433. Random match probability is 0.0381.Gene diversity is 0.09680. HV1B: Among the 104 unrelated individuals from HeBei Han Population, 25 types were observed. The gene type frequencies were between 0.009615-0.1442. Random match probability is 0.0793.Gene diversity is 0.9296. HV2A: Among the 100 unrelated individuals from HeBei Han Population, 22 gene types were observed. The gene type frequencies were between 0.01-0.18. Random match probability is 0.0914.Gene diversity is 0.9178. HV2B: Among the 101 unrelated individuals from HeBei Han Population, 19 gene types were observed. The gene type frequencies were between 0.009901-0.1881. Random match probability is 0.0873. Gene diversity is 0.9218. Coding region encompassing position 8430-8673: Among the 175 unrelated individuals, 29 gene types were observed. The gene type frequencies were between 0.0057-0.1657. Random match probability is 0.0936. Gene diversity is 0.9116. Combined these mtDNA fragments, 91 gene types were noted among 100 unrelated individuals, of which 8gene types were shared by two individuals.Compared to the Anderson sequence,65 sites of different nucleotide sequence were noted among which 44 sites were previously registered in MITOMAP and 12 sites were not registered in it ,as follows:...
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