This study was undertaken to figure out the basic patterns of the frequency distribution of Ascaris lumbricoides in rural Koreans and to find out the effects of changing endemicity on the frequency distribution pattern. Total 853 cases in 6 areas were surveyed from November 1975 to February 1978. The mean ova positive rate was 33.1% and in the range from 23.9 to 66.7% by the surveyed unit. From the analyses of the collected data, the following results were obtained. The overdispersion pattern of worm burden per case was mathematically fitted both to the theoretical values of the negative binomial and Poly-Eggenberger distributions. However, when "0" and lower burden cases were considered, the better fitness was observed in the negative binomial than in Polya-Eggenberger distribution. Although the endemicity of Ascaris is changed, the relative frequency of the lower burden cases is rather constant. The false negative rate of stool examination and unfertilized ova passers in the population were not changed significantly according to the endemicity. And the rate of unfertilized ova passers in infected cases was increased when the endemicity was lowered. From the above results, it is concluded that the overdispersed frequency distribution pattern of Ascaris in an endiemic area is changed by the relatively rapid decrease of heavy burden cases and increase of non-infected cases according to the lowered endemicity due to the impact of the control.
parasitology-helminth-nematoda ; Ascaris lumbricoides ; egg ; epidemiology ; frequency distribution

Since the pattern of the frequency distribution of a parasite within a host showed an overdispersed pattern, various statistical models such as Poisson, negative binomial and lognormal distributions have been applied on the population dynamics in host-parasite relations. The observed data on the number of metacercariae of Clonorchis sinensis in a suitable intermediate host, Pseudorasbora parva which were collected from an endemic area, Juk-Rim River, Kim-Hae Goon, South Kyong-Sang Do were applied on the statistical models. The results obtained are as follows: By the calculation of the raw data, 258(94.9 percent) out of 272 fish showed positive to the metacercarial infection of C. sinensis. The mean number of metacercaria in a fish was 335.1. The standard deviation was 250.6 and the mode was observed between 250 and 299. The frequency distribution pattern of metacercariae of C. sinensis within the fish host in surveyed area was fitted to the lognormal distribution (0.05distribution. From the above statistical analyses, it was concluded that the lognormal distribution was selected as a distribution pattern of metacercariae of C. sinensis in their suitable fish host.
parasitology-helminth-trematoda ; Clonorchis sinensis ; metacercaria ; Pseudorasbora parva ; frequency distribution ; host

The apolipoprotein E (APOE) epsilon4 allele is a known risk factor for the development of Alzheimer's disease, however, an association of the APOE genotype with schizophrenia is controversial. We investigated the association in 60 Korean schizophrenic patients and 60 healthy controls. APOE genotypes were identified by reverse hybridization-based line probe assay. There were significant differences in the distribution of APOE genotypes between schizophrenic patients and controls. APOE epsilon2 and epsilon3 allele frequencies in schizophrenic patients were significantly different from those in controls. Our results suggest that APOE alleles seem to be operative in the pathogenesis of schizophrenic disorders.
Adult ; Age Distribution ; Apolipoproteins E/*genetics ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Human ; Korea ; Male ; Risk Factors ; Schizophrenia/*epidemiology/*genetics ; Sex Distribution

This article review the application of chi-square test of various data handling methods and exact test in Hardy-Weinberg equilibrium testing of human genetic marker in population genetics. The importance of HWE-exact test in multiallelic system was emphasized, especially in the study of forensic VNTR and STR typing.
Alleles ; Chi-Square Distribution ; Forensic Medicine ; Gene Frequency ; Genetics, Population/methods* ; Genotype ; Humans ; Likelihood Functions ; Models, Genetic ; Models, Statistical

OBJECTIVE: To calculate the exclusion power of STR loci in motherless parentage testing and to discuss how to draw a conclusion if there are inconsistent loci. METHODS: Based on the law of inheritance and allele frequency, the powers of exclusion of STR loci in motherless parentage testing (PE(M)) were calculated. Based on the mean PE(M) and mutation rate of 13 CODIS loci. The probabilities of inconsistence under paternity and non-paternity were calculated respectively according to binomial theorem. RESULTS: The PE(M) of locus having co-dominate alleles could be calculated as: PE(M) = (i = 1)sigma (n) p i 2(1-p (i))2+ (i < j)sigma (n) 2p (i)p (j)(1-p (i)-p (j))2. According to the formula, the average PE(M) of 13 CODIS was 0.411. Based on the mean PE(M) and mutation rate, the likelihood ratio of true father to random man (paternity index) was got using binomial theorem. CONCLUSION The conclusion in motherless parentage testing could be drawn based on the likelihood ratio (paternity index) derived from mean PE(M) and mutation ratio.
Algorithms ; Alleles ; Binomial Distribution ; Forensic Genetics/methods* ; Gene Frequency ; Genetic Markers ; Humans ; Male ; Mutation ; Paternity ; Probability ; Tandem Repeat Sequences

OBJECTIVETo add DXS7133, GATA198A10, DXS9896 and DXS6797 to the panel of forensically validated X chromosome markers, and apply the multiplex amplification system to a population study and forensic analysis on the Hans of Chengdu.

METHODSThe PCR products were detected by the polyacrylamide gel electrophoresis and silver staining method. Hardy-Weinberg equilibrium of females was tested and every forensically interested value was calculated.

RESULTSSequencing revealed that their common sequence motifs were tetranucleotide repeats. Population genetic data were obtained by analyzing 120 unrelated females and 100 males from Chengdu Han ethnic group. In this population, DXS7133, GATA198A10, DXS9896 and DXS6797 exhibited 6, 6, 11, 8 distinguishable alleles respectively. Chi-square test demonstrated that genotype frequencies in females did not depart from Hardy-Weinberg equilibrium. Power of discrimination for female samples for the four loci were 0.7962, 0.8021, 0.9675, and 0.9444. The parentage testing in 32 cases revealed a typical X-linked inheritance and no mutations.

CONCLUSIONDXS7133, GATA198A10, DXS9896 and DXS6797, which are highly polymorphic in Chengdu Han population, are appropriate for individual identification and paternity testing involving a female child.

Asian Continental Ancestry Group ; genetics ; Chi-Square Distribution ; China ; Chromosomes, Human, X ; genetics ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Microsatellite Repeats ; genetics ; Polymerase Chain Reaction ; Polymorphism, Genetic ; genetics

To clarify the association between HLA-DPB1 alleles and chronic myelogenous leukemia (CML) in South Chinese, the allelic types of HLA-DPB1 were detected by sequence based typing (SBT) in 86 patients with CML and 82 healthy individuals from Southern China. The results showed that the frequencies of HLA-DPB1 * 1301 and DPB1 * 20011 were higher in patients with CML in comparison with those of healthy individuals. It is concluded that positive association may exist between certain HLA-DPB1 alleles and CML.
Alleles ; Chi-Square Distribution ; China ; Gene Frequency ; Genotype ; HLA-DP Antigens ; genetics ; HLA-DP beta-Chains ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; genetics

OBJECTIVETo assess the value of 15 short tandem repeat (STR) loci selected by an AmpFLSTR Identifilersystem for personal identification and paternity testing among ethnic Hans from Xiamen, Fujian.

METHODSFor 400 unrelated individuals, allelic frequencies for the 15 STR loci from the AmpFLSTR Identifilerkit were determined. Population genetics parameters for forensic usage were calculated.

RESULTSNo deviation of the observed allele frequency from Hardy-Weinberg equilibrium expectations was found by Chi-square test (P>0.05). All of the 15 loci were highly polymorphic. Observed heterozygosity has varied between 0.580 and 0.868. Matching probability was between 0.036 and 0.148. Power of discrimination was between 0.798 and 0.967. Polymorphic information content was between 0.560 and 0.850. And power of exclusion was between 0.268 and 0.730.

CONCLUSIONAll of the 15 loci selected by the AmpFLSTR Identifilersystem are highly polymorphic among ethnic Hans from Xiamen. By determining the alleles and allelic frequencies, data for genetic polymorphisms usable for paternity testing and personal identification for local population were obtained.

Alleles ; Asian Continental Ancestry Group ; genetics ; Chi-Square Distribution ; China ; Forensic Genetics ; methods ; Gene Frequency ; Genetics, Population ; methods ; Genotype ; Humans ; Linkage Disequilibrium ; Microsatellite Repeats ; genetics ; Polymorphism, Genetic

OBJECTIVETo introduce the design and statistical methods of case-sibling control design and to analyze the published data.

METHODSData from an association study between the coronary heart disease and methylenetetrahydrofolate reductase gene C677T polymorphism was analyzed by the sib transmission/disequibrium test (s-TDT) and the sibship disequilibrium (SDT) methods.

RESULTSUsing s-TDT method, Z value was 0.27 with P > 0.05. The result of SDT method showed that chi-square was 0.31 with 1 df, P > 0.05. All results suggested that neither s-TDT nor SDT showed significant difference between the transmitted and untransmitted methylenetetrahydrofolate reductase gene C677T allele distributions.

CONCLUSIONCase-sibling control design might avoid population stratification by using siblings as controls thus might be used to test association and linkage between genes and disease.

Case-Control Studies ; Chi-Square Distribution ; Coronary Disease ; genetics ; Epidemiologic Methods ; Gene Frequency ; Genetic Association Studies ; Genetic Linkage ; Humans ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Polymorphism, Genetic ; Research Design ; Siblings

OBJECTIVETo analyze the distribution of matrix metalloproteinase-3 (MMP-3) genotype and its association with the blood pressure profiles in Guangzhou rural population.

METHODSThis study was conducted among 680 rural residents aged 40-70 years (including 314 men and 366 women) from 3 villages in an rural area of Guangzhou. The blood pressures of the subjects were measured and blood samples were collected for genotype analysis using polymerase chain reaction and direct sequencing of the MMP-3 gene promoter region to detect the 5 adenines (5A)/6 adenines (6A) polymorphisms.

RESULTSThe frequencies of MMP-3 genotypes 6A/6A, 5A/5A, and 5A/6A were 82.6%, 1.8% and 15.6% among these residents, respectively. The distribution of MMP-3 genotypes and allele frequencies showed no significant gender- or age-related variations. The men with different genotypes (6A/6A vs 5A/6A+5A/5A) did not show significant differences in blood pressure levels, whereas the women with 5A/6A+5A/5A genotypes had higher systolic and diastolic blood pressures than those with a 6A/6A genotype. The allele 5A was highly frequent in the hypertensive residents as compared with the normotensive residents.

CONCLUSIONSThe 6A homozygote is the predominant genotype of MMP-3 in Guangzhou rural population, which has a significantly lower proportion of 5A homozygote than the Western populations. The 5A allele is associated with a high risk of hypertension especially in women and may affect both systolic and diastolic blood pressures.

Adult ; Age Distribution ; Aged ; Alleles ; Blood Pressure ; China ; epidemiology ; Female ; Gene Frequency ; Genotype ; Humans ; Hypertension ; epidemiology ; genetics ; Male ; Matrix Metalloproteinase 3 ; genetics ; Middle Aged ; Risk Factors ; Rural Population ; Sex Distribution