ABSTRACT
<p><b>OBJECTIVE</b>To investigate the genetic polymorphisms of 12 X chromosome short tandem repeat (X-STR) loci of Investigator Argus X-12 amplification kit in Guangdong Han population.</p><p><b>METHODS</b>DNA samples from 200 unrelated individuals (100 males and 100 females) and 103 families (59 father-mother-daughter trios and 44 mother-son duos) were extracted and amplified with fluorescence labeled multiplex PCR system. PCR products were separated and genotyped with capillary array electrophoresis.</p><p><b>RESULTS</b>One hundred and thirty-seven alleles,including 9 off ladder alleles (OL allele) were observed at the 12 X-STR loci in the population. Six mutations were observed in 162 meioses. The combined power of discrimination (DP) was 0.999 999 997 in males and 0.999 999 999 in females, and the combined mean exclusion chance (MEC) was 0.999 999 988 in the trio cases and 0.999 998 013 in the duo cases.</p><p><b>CONCLUSION</b>Investigator-Argus X-12 amplification system is highly polymorphic in Guangdong Han population and it is powerful for personal identification and paternity testing.</p>
Subject(s)
Female , Humans , Male , Alleles , China , Chromosomes, Human, X , Gene Amplification , Gene Frequency , Genetics, Population , Genotype , Microsatellite Repeats , Mutation , Paternity , Polymerase Chain Reaction , Methods , Polymorphism, Genetic , RecordsABSTRACT
OBJECTIVE@#To explore the distribution and genetic pattern of heteroplasmy of mtDNA control region among Chinese Han population.@*METHODS@#The human mtDNA control region was amplified into 6 amplicons overlapped partially each other. Then these amplicons were analyzed by DHPLC which we developed to detect low heteroplasmic signals.@*RESULTS@#There were 51 heteroplasmic cases (34%) found from different tissues of 150 unrelated individuals of the Chinese Han population. mtDNA heteroplasmy shows non-uniform distribution in various tissues. The highest occurrence of heteroplasmy was in brain tissues (50/150) and myocardium (48/150), the lowest was in bone tissues (22/150). 36 sites of heteroplasmy were identified in our samples. Three sites of mtDNA heteroplasmy rarely co-existed in one individual. No sex differences were detected in the frequency of mtDNA heteroplasmy. No change in the mtDNA heteroplasmy profile was detected of blood samples from the same individuals within 2 years. Individuals older than 41 years showed a heteroplasmy frequency significantly higher than their younger counterparts. Members from the same maternal pedigree in a family can share the same sites of mtDNA heteroplasmy but may have different heteroplasmy contents at those sites.@*CONCLUSION@#DHPLC is a highly sensitive technique in detecting heteroplasmy. mtDNA heteroplasmy widely exists in the Chinese Han population. The results shown here could potentially have a guidable value in forensic individual identification and parentage testing.
Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Child , Humans , Middle Aged , Young Adult , Asian People/genetics , Base Sequence , Blood Stains , China/ethnology , Chromatography, High Pressure Liquid/methods , DNA Mutational Analysis/methods , DNA, Mitochondrial/genetics , Genetic Heterogeneity , Hair/chemistry , Mutation , Polymorphism, Genetic/geneticsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the applicability of the polymorphic marker closely linked with beta-globin gene for the preimplantation genetic diagnosis (PGD) in couples at risk of having child with beta-thalassemia.</p><p><b>METHODS</b>Single cell multiplex nested PCR which coamplifies the beta-globin gene and the closely linked polymorphic marker, HumTHO1 gene, was applied in six clinical PGD cycles for four couples with beta-thalassemia.</p><p><b>RESULTS</b>In six clinical PGD cycles, a total of 44 embryos were biopsied and 44 blastomeres were obtained. Forty-one blastomeres were amplified and thirty-five embryos were given definite diagnoses. Fourteen embryos were transferred back to the uterus of the patients and one pregnancy went on well and ended with one live healthy birth, which confirmed the results of PGD. The average amplification efficiency of single blastomere was 89.7% and the average allele drop-out(ADO) rate was 14.4%. The coamplification of HumTHO1 could help to detect the existence of ADO and contamination.</p><p><b>CONCLUSION</b>This is the first report on unaffected pregnancy resulting from PGD using multiplex nested PCR in China. The simultaneous amplification of polymorphic marker closely linked to beta-globin gene(HumTHO1) could help to resist the risk of misdiagnosis in PGD caused by ADO and contamination.</p>
Subject(s)
Adult , Female , Humans , Male , Pregnancy , Polymerase Chain Reaction , Preimplantation Diagnosis , Methods , beta-Globins , Genetics , beta-Thalassemia , Diagnosis , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To explore the mutations of 15 short tandem repeat (STR) loci in PlowerPlex16 System which are world-widely used in parentage testing.</p><p><b>METHODS</b>Mutations of 15 STR loci in PlowerPlex16 System were investigated in 1921 parentage testing cases from Chinese population.</p><p><b>RESULTS</b>In 1921 parentage cases, seventy cases (3.644%) were found to have mutations. Among these were one case with double mutations (D21S11 and PentaD) and another case with two different mutations (D7S820 and D16S539) in two children. The total number of mutated STR loci observed was 72 over 3764 meiosis with a mutation rate of 0.128% +/- 0.1104% x 10(-3). The highest mutation rate was 0.292% at vWA and D21S11. No mutation was observed at TH01 or at TPOX. The mutated alleles coming from father were five times more than those from mother. The majority (98.611%) of mutated alleles were the results of one-step mutation. The ratio of one-step gain versus loss was 1.826:1. There was only one multiple-step mutation with a double-repeat gain observed at PentaD locus. In the PlowerPlex16 System, nine loci, namely D8S1179, Penta D, D13S317, D16S539, D7S820, D5S818, D3S1358, TH01 and TPOX, have lower mutation rates and are more suitable for parentage testing.</p><p><b>CONCLUSION</b>Mutation of STR is relatively common and often makes parentage testing more complicated. Selecting stable STR locus with low mutation rate is more important in parentage testing.</p>
Subject(s)
Humans , Alleles , Asian People , Genetics , China , Genetics, Population , Microsatellite Repeats , Genetics , Mutation , Polymerase Chain ReactionABSTRACT
OBJECTIVE@#To accumulate experience for dated forensic matter analysis, for example, Mummy.@*METHODS@#DNA are extracted by methods of phenol-chloroform and are purified by Wizard DNA clean-up system. The STRs locus are ampolification with Promega Powerplus 16 system. The mtDNA hypervariable region 1 (HV1) is amplificated by '3 pair primers'. The products were sequenced with 377 DNA sequencer.@*RESULTS@#The STRs locus very distinctness and mtDNA sequence is correct.@*CONCLUSION@#It is a valuable method for special forensic matters.