OBJECTIVETo analyze related factors which affect GPA mutation frequency of workers exposed to benzene, with the Glycophorin A (GPA) mutation assay and explore the possibility of GPA mutation frequency as an index of predicting the risk of benzene poisoning.

METHODSThe erythrocytes were bound with fluorescent-labeled monoclonal antibody after isolated and fixed from the peripheral blood, and then the GPA mutation assay was performed using the flow cytometry (FCM). The related factors of GPA mutation frequency were analyzed by statistical methods.

RESULTSThe GPA mutation frequency of chronic benzene poisonings was significantly higher than that of their controls (P < 0.05). Significant direct correlation was found between age, length of service, accumulative exposure score and the GPA mutation frequency of workers exposed to benzene (P < 0.01). However, there was significantly inverse correlation between the 3AB index and the GPA mutation frequency (GPAN0: r(s) = -0.589, P < 0.01, GPANN: r(s) = -0.615, P < 0.01). In the multiple factor regression analysis on GPA mutation frequency, benzene exposure and individual susceptibility both entered model of multiple factors analysis, the coefficient of determination of benzene-exposed workers was 0.819.

CONCLUSIONExposure to benzene and individual susceptibility are the most important factors that affect GPA mutation frequency. GPA mutation frequency increases with the benzene exposure and individual susceptibility.

Benzene ; poisoning ; Glycophorin ; genetics ; Humans ; Mutation ; Mutation Rate ; Occupational Exposure

OBJECTIVE: To study the instability of mitochondrial DNA（mt DNA） D-loop region genes in patients with Leukemia. METHODS: The HV-1 and HV-2 regions of D-loop region in 24 patients with leukemia were amplificated and sequenced, then their results were compared with revised Cambridge reference sequence (rCRS) and Databank mtDB. The mutation rate was detected by SPSS 22.0 statistics software. RESULTS: The total mutation rate in patients was 95.83% (23/24), the detection showed 82 mutated genes, out of which 47 (57.32%) mutated genes located in HV-1 region, 35 (42.68%) mutated genes in HV-2 region. The comparison showed that the mutation rate in untreated (UT) group and treated (T) group of AML patients was (2.37±0.82)×10 and (4.76±2.45)×10 respectively(P＜0.01), the mutation rate in PR and CR groups of treated AML patients was (5.10±2.56)×10 and (4.51±2.51)×10 respectively (P＜0.05), the comparison among M3 group showed that the mutation rates in UT, PR and CR groups were (2.55±0.63)×10, (5.37±3.41)×10 and (3.71±1.65)×10 respectively (P＞0.05). CONCLUSION The more high mutation rate and many kinds of mutation types exist in D-loop region, suggesting that the genes in D-loop region display the more strong instability, the chemotherapy may aggravate the instability of genes in D-loop region.
DNA, Mitochondrial ; Humans ; Leukemia ; Mitochondria ; Mutation ; Mutation Rate

The aim of this study was to validate the sex typing based on amplification of X-Y homologous Amelogenin locus in Korean including mutation rate in this locus. It was found that there was no case with reported mutation that may hinder the exact sex typing among 240 Koreans, and the sex typing was successful even with subnanogram quantities of male and female DNA. There was no difference in the sensitivity of reaction among male and female. Differential amplification between X and Y amelogenin bands in some samples was noted, and dilution study revealed that this phenomenon was more frequent when the quantity of sample was low, usually less than 10 ng. That phenomenon was variable between amplification reactions, and was also dependent on different Taq enzyme used for the amplification. When there was differential amplification, the intensity ratio (Y band/X band) ranged about 0.68 - 0.87.
Amelogenin* ; DNA ; Female ; Humans ; Male ; Mutation Rate

We have investigated 17 Y-STR loci (DYS19, DYS385a/b, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 (Y GATA C4), Y GATA H4) in 365 Korean father-son pairs of 355 families. Of 338 different haplotypes obtained from 355 fathers, 326 haplotypes were observed once, 10 haplotypes two times and the other two haplotypes were observed 4 and 5 times, respectively. The overall haplotype diversity was 0.9996. In 365 father-son pairs, a total of 21 mutations were observed at 12 Y-STR loci. Sequence analysis for mutant alleles demonstrated 21 single step mutations: 8 gains and 13 losses. However, there was no significant surplus of gains or losses. The locus-specific mutation rate estimates were between 0.0 and 8.2 x 10(-3) and the average mutation rate estimates were 3.4 x 10(-3)(95% C.I. 2.1-5.2 x 10(-3)) across all 17 Y-STR loci.
Alleles ; Fathers ; Haplotypes* ; Humans ; Mutation Rate ; Sequence Analysis

OBJECTIVETo analyze the mutation rate and clinical characteristics of CALR, MPL W515K and JAK2 V617F genes in patients with primary thrombocythemia (PT).

METHODSFifty-six patients with PT were selected as the research objects in our hospital. The CALR and MPL W515K gene mutations were determined by genomic DNA-PCR direct sequencing of the PCR products, and the JAK2 V617F gene mutation was detected by allele specific PCR method.

RESULTSAmong the 56 patients with PT there were 14 cases of CALR gene mutation with the incidence rate of 25%, including 6 cases of type I, 5 cases of type II and 3 cases of type III. The sex, age, platelet(Plt) count, white blood cell (WBC) count and hemoglobin (Hb) level in the type I case of CALR gene mutation all were not significantly different from that in type II and III(all P>0.05); the WBC level in type III group significantly increased in comparison of type II group (P<0.05), while the sex, age, Hb and Plt levels showed no significant difference between the type III and type II groups (P>0.05). There were 3 cases of MPL W515K gene mutation with the incidence rate of 5.36%; 21 cases of JAK2 V617F gene mutation with the incidence rate of 37.50%. There were 13 cases of CALR gene mutation in negative patients with MPL W515K and JAK2 V617F (18 cases) with 72.22% incidence rate (13/18), and there was no cases of 1 or 2 gene mutations coexisted. The levels of Hb and WBC in peripheral blood of patients with CALR mutation were significantly lower than those of JAK2 V617F mutation (both P<0.05). In 56 cases, there were 3 cases of abnormal karyotype, with the incidence rate of 5.36%. The mutation rate of CALR gene in abnormal karyotypes (66.67%) was significantly higher than that of normal karyotypes (20.75%) (P<0.01).

CONCLUSIONThe incidence of JAK2 V617F gene mutation increases in the patients with primary thrombocythemia; CALR mutation rate is higher in the patients with negative MPL W515K and JAK2 V617F gene mutation, which may closely correlate with abnormal karyotype; the levels of peripheral Hb and WBC in PT the patients with CALR gene mutation are significantly lower than those in patients with JAK2 V617F mutation.

Calreticulin ; Humans ; Janus Kinase 2 ; Mutation ; Mutation Rate ; Receptors, Thrombopoietin ; Thrombocythemia, Essential

OBJECTIVES: To observe and analyze the confirmed cases of paternity testing, and to explore the mutation rules of STR loci. METHODS: The mutant STR loci were screened from 20 723 confirmed cases of paternity testing by Goldeneye 20A system．The mutation rates, and the sources, fragment length, steps and increased or decreased repeat sequences of mutant alleles were counted for the analysis of the characteristics of mutation-related factors. RESULTS: A total of 548 mutations were found on 19 STR loci, and 557 mutation events were observed. The loci mutation rate was 0.07‰-2.23‰. The ratio of paternal to maternal mutant events was 3.06:1. One step mutation was the main mutation, and the number of the increased repeat sequences was almost the same as the decreased repeat sequences. The repeat sequences were more likely to decrease in two steps mutation and above. Mutation mainly occurred in the medium allele, and the number of the increased repeat sequences was almost the same as the decreased repeat sequences. In long allele mutations, the decreased repeat sequences were significantly more than the increased repeat sequences. The number of the increased repeat sequences was almost the same as the decreased repeat sequences in paternal mutation, while the decreased repeat sequences were more than the increased in maternal mutation. CONCLUSIONS There are significant differences in the mutation rate of each locus. When one or two loci do not conform to the genetic law, other detection system should be added, and PI value should be calculated combined with the information of the mutate STR loci in order to further clarify the identification opinions.
Alleles ; DNA Mutational Analysis/methods* ; Family ; Genetic Loci ; Humans ; Male ; Microsatellite Repeats ; Mutation ; Mutation Rate ; Paternity

BACKGROUND: Clarithromycin resistance in Helicobacter pylori is a major cause of eradication therapy failure. The objective of this study was to determine the frequency and type of mutations in the 23S rRNA gene in Korea, which are associated with clarithromycin resistance. METHODS: From January 2008 to March 2008, 353 gastric biopsy specimens were collected from five university hospitals in Seoul and Kyunggido. H. pylori infection was defined as showing a positive result in at least one of the following three tests: a microaerophilic culture, a CLO test, and a Giemsa/silver stain. The frequencies of A2143G, A2142G, and the wild type of 23S rRNA and the presence of H. pylori were determined by Seeplex ClaR-H. pylori PCR (Seegene Inc., Seoul, Korea). Twenty-nine culture isolates were tested for susceptibility to clarithromycin by E-test (AB Biodisk, Solna, Sweden) or the CLSI (Clinical and Laboratory Standards Institute) disk diffusion test. RESULTS: From 176 H. pylori PCR-positive specimens, 23S rRNA gene mutations were detected in 38 isolates (21.6%), including 27 isolates of A2143G and 11 isolates of A2142G. Total mutation rates varied from 15.8% to 31.3% with the frequency of A2143G mutation alone varying from 8.5% to 25.0% among the five hospitals studied. There were 10 clarithromycin-resistant isolates found by susceptibility test and they were all positive for A2143G mutation. But, 3 of the 19 susceptible isolates were also positive for either A2143G or A2142G mutation. CONCLUSION: In Korea, the overall frequency of clarithromycin-resistant H. pylori was 21.6%; however, the type and frequency of the 23S rRNA mutations varied from hospital to hospital.
Biopsy ; Clarithromycin ; Diffusion ; Genes, rRNA ; Helicobacter ; Helicobacter pylori ; Hospitals, University ; Korea ; Mutation Rate ; Point Mutation ; Polymerase Chain Reaction

PURPOSE: Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumor, and express the KIT protein. Previous studies have reported KIT phosphorylation to be the principal biological event in the tumoriogenesis of GIST, which is generally evoked by the conformational mutation of KIT receptors. The aim of this study was to evaluate the frequency and category of c-kit mutations and their prognostic relevance. METHODS: The frequency and category of the c-kit mutations and the correlation between clinical outcome and the c-kit mutations were analyzed and the significance of the c-kit mutations examined as independent prognostic factors in 84 cases of GIST. The c-kit mutations were measured by polymerase chain reaction and DNA sequencing, using an ABI 3700 sequencer. RESULTS: c-kit mutations were noted in 14 of the 84 cases (16.7%) of GIST. Mutations in exon 11 were found in 11 cases (78.6%), exon 9 in 2 (14.3%) and exon 13 in 1 (7.1%), but no mutation was noted in exon 17. Of the mutations in exon 11, missense mutations were observed in 9 cases and frameshift mutations in 2. Among the 14 cases with c-kit mutations, 1 (7.1%) was found in a very low risk patient, 4 (28.6%) in intermediate risk patients and 9 (64.3%) in high risk patients. The c-kit mutations were observed more frequently in high risk patients (P=0.0366). However, there was no significant difference between the c-kit mutations and the survival rate. CONCLUSION: These results suggest that kit mutations might have a pathogenetic role in GIST, 550~560 in exon 11 of c-kit gene is the conserving area of mutation and c-kit mutations are uncertain as prognostic factors in GIST. However, further study will be required.
Exons ; Frameshift Mutation ; Gastrointestinal Stromal Tumors* ; Humans ; Mutation, Missense ; Phosphorylation ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Survival Rate

PURPOSE: Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumor, and express the KIT protein. Previous studies have reported KIT phosphorylation to be the principal biological event in the tumoriogenesis of GIST, which is generally evoked by the conformational mutation of KIT receptors. The aim of this study was to evaluate the frequency and category of c-kit mutations and their prognostic relevance. METHODS: The frequency and category of the c-kit mutations and the correlation between clinical outcome and the c-kit mutations were analyzed and the significance of the c-kit mutations examined as independent prognostic factors in 84 cases of GIST. The c-kit mutations were measured by polymerase chain reaction and DNA sequencing, using an ABI 3700 sequencer. RESULTS: c-kit mutations were noted in 14 of the 84 cases (16.7%) of GIST. Mutations in exon 11 were found in 11 cases (78.6%), exon 9 in 2 (14.3%) and exon 13 in 1 (7.1%), but no mutation was noted in exon 17. Of the mutations in exon 11, missense mutations were observed in 9 cases and frameshift mutations in 2. Among the 14 cases with c-kit mutations, 1 (7.1%) was found in a very low risk patient, 4 (28.6%) in intermediate risk patients and 9 (64.3%) in high risk patients. The c-kit mutations were observed more frequently in high risk patients (P=0.0366). However, there was no significant difference between the c-kit mutations and the survival rate. CONCLUSION: These results suggest that kit mutations might have a pathogenetic role in GIST, 550~560 in exon 11 of c-kit gene is the conserving area of mutation and c-kit mutations are uncertain as prognostic factors in GIST. However, further study will be required.
Exons ; Frameshift Mutation ; Gastrointestinal Stromal Tumors* ; Humans ; Mutation, Missense ; Phosphorylation ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Survival Rate

OBJECTIVETo investigate the genotoxicity of bone cement.

MATERIAL AND METHODSTest article was mixed of liquid and the powder extract of bone cement. Using bacterial reverse mutation test (Ames test) and mouse lymphoma Assay (MLA) with and without metabolic activation S9. Ames test was performed by the plate incorporation method for its ability to induce reverse mutations in three treatment dosage groups: 25 microl/plate, 50 microl/plate, 100 microl/plate using S. typhimurium TA98, TA100, TA1535, TA1537 and E. coli WP2 uvrA; In MLA, the mutation frequency (MF) and the percentage of small colony mutants (SC%) of L5178 tk(+/-) cells induced by bone cement at final concentration of 0.125%, 0.25% and 0.5% (V/V) were calculated and assayed with +S9/3 h, - S9/3 h, -S9/24 h.

RESULTSSlight precipitations of two dosage group 50 microl/plate and 100 microl/plate were observed after phosphoric acid buffer solution or S9mix added. Growth inhibition effect exists in TA100, TA1535 and WP2 uvrA to varying degrees. Other groups did not cause obvious increases in the mean number of revertant per plate compared with negative control (DMSO). The result of MLA indicated no significant MF or SC% increases (P>0.05) observed comparing with negative control under all test conditions.

CONCLUSIONSThe bone cement did not induce reverse mutation at his(-)/trp(-) and there was no obvious damage effect to gene tk(+/-) or chromosome under this study condition.

Animals ; Bone Cements ; toxicity ; Cell Line, Tumor ; DNA Damage ; Mice ; Micronucleus Tests ; Mutagens ; toxicity ; Mutation ; Mutation Rate ; Salmonella