• The Korean Journal of Applied Statistics
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• v.23 no.6
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• pp.1103-1113
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• 2010

An extensively used approach for family based association test(FBAT) is compared with the sib transmission/disequilibrium test(S-TDT), and in particular the adjusted S-TDT, in which the covariance among related siblings is taken into consideration, can provide a more sensitive test statistic for association. A simulation study comparing the three test statistics demonstrates that the type I error rates of all three tests are larger than the prespecified significance level and the power of the FBAT is lower than those of the other two tests. More detailed studies are required in order to assess the influence of the assumed conditions in FBAT on the efficiency of the test.

• Journal of Preventive Medicine and Public Health
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• v.37 no.4
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• pp.366-372
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• 2004

Objectives : This study was conducted to propose a new transmission/disequilibrium test(TDT) to test the linkage between genetic markers and disease-susceptibility genes based on haplotypes. Simulation studies were performed to compare the proposed method with that of Zhao et al. in terms of type I error probability and powers. Methods : We estimated the haplotype frequencies using the expectation-maximization(EM) algorithm with parents genotypes taken from a trio dataset, and then constructed a two-way contingency table containing estimated frequencies to all possible pairs of parents haplotypes. We proposed a score test based on differences between column marginals and their corresponding row marginals. The test also involved a covariance structure of marginal differences and their variances. In simulation, we considered a coalescent model with three genetic markers of biallele to investigate the performance of the proposed test under six different configurations. Results : The haplotype-based TDT statistics, our test and Zhao et al.'s test satisfied a type I error probability, but the TDT test based on single locus showed a conservative trend. As expected, the tests based on haplotypes also had better powers than those based on single locus. Our test and that of Zhao et al. were comparable in powers. Conclusion : We proposed a TDT statistic based on haplotypes and showed through simulations that our test was more powerful than the single locus-based test. We will extend our method to multiplex data with affected and/or unaffected sibling(s) or simplex data having only one parent s genotype.

• Communications for Statistical Applications and Methods
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• v.24 no.6
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• pp.663-671
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• 2017

Some genetic association tests include an unidentifiable nuisance parameter under the null hypothesis of no association. When the mode of inheritance (MOI) is not specified in a case-control design, the Cochran-Armitage (CA) trend test contains an unidentifiable nuisance parameter. The transmission disequilibrium test (TDT) in a family-based association study that includes the unaffected also contains an unidentifiable nuisance parameter. The hypothesis tests that include an unidentifiable nuisance parameter are typically performed by taking a supremum of the CA tests or TDT over reasonable values of the parameter. The p-values of the supremum test statistics cannot be obtained by a normal or chi-square distribution. A common method is to use a Davies's upper bound of the p-value instead of an exact asymptotic p-value. In this paper, we provide a unified sine-cosine process expression of the CA trend test that does not specify the MOI and the TDT that includes the unaffected. We also present a closed form expression of the exact asymptotic formulas to calculate the p-values of the supremum tests when the score function can be written as a linear form in an unidentifiable parameter. We illustrate how to use the derived formulas using a pharmacogenetics case-control dataset and an attention deficit hyperactivity disorder family-based example.

• The Korean Journal of Applied Statistics
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• v.18 no.2
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• pp.297-310
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• 2005

In this study we investigate the association between the haplotype block of 4 SNPs in ACE genes and hypertension with a case-control dataset of size of 277 and 40 families data collected from Kangwha studies. To this end we perform a haplotype-based case-control association study and a haplotype-based TDT study. We do the same analysis with tag-SNPs that can identify the haplotype block. Through a cladogram analysis we make the evolution-tree of haplotypes and then classify the haplotypes into a few clades by collecting haplotypes exposed to the disease to the same extent. We also discuss the association between these clades and hypertension.

• Korean Journal of Biological Psychiatry
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• v.13 no.4
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• pp.289-298
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• 2006

Objectives : Autism is a complex neurodevelopmental spectrum disorder with a strong genetic component. Previous neurochemical and genetic studies suggested the possible involvement of glutamate N-methyl-D-aspartate(NMDA) receptor in autism. The aim of study was to investigate the association between the NMDA2B receptor gene(GRIN2B) and autism spectrum disorders(ASD) in the Korean population. Methods : The patients with ASD were diagnosed with Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule based on DSM-IV diagnostic classification. The present study was conducted with the detection of four single nucleotide polymorphisms(SNPs) in GRIK2 and family-based association analysis of the single nucleotide polymorphisms in Korean ASD trios using transmission disequilibrium test (TDT). Results : One hundred twenty six patients with ASD and their biological parents were analyzed. 86.5% were male and 85.1% were diagnosed as autistic disorder. The mean age was $71.9{\pm}31.6$ months(range : 26-185 months). We found that rs1805247 showed significantly preferential transmission(TDT ${\chi}^2$=12.8, p<0.001) in ASD. Conclusion : One SNP in GRIN2B gene was significantly associated with ASD in the Korean population. This result suggests the possible involvement of glutamate NMDA receptor gene in the development of ASD.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.15 no.2
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• pp.178-184
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• 2004

Objectives : This study was conducted to investigate the association of the COMT polymorphism with the TD in Korean sample of families with TD probands. The relationship between risk alleles and specific clinical features (tic severity, comorbidity, drug response) was also explored. Method : Patients were recruited from the Tic Disorder clinic at the Child & Adolescent Psychiatric Division of Seoul National University Hospital and assessed through 2 stage evaluation. Firstly, all the patients and parents received semistructured interview using Korean version of K-SADS-PL. Secondly all the patients received clinical interview and tic severity assessment with Korean version of YGTSS. The subjects in control group were recruited from the health promotion center in out hospital and were evaluated by SCL-90 and SCID-IV. Through these process, total of 42 children and adolescents with TD, their 84 parents and 86 control subjects were finally recruited. Genotyping for The Val158Met polymorphism of the COMT gene was done by standardized method. After collection of genetic data of all the patients, parents and control subjects, case-control comparison and tranmission dysequilibrium test was executed by SPSS version 11. Result : From the case-control comparison, the frequency of L-allele and LL genotype was significantly higher in TD group. However, no differences were found from the TDT. No significant differences were found in in family history of tic, ADHD, OCD, drug response and comorbid conditions among the three different genotypes in patients with TD. Conclusion : Though this study results should be interpreted cautiously due to small sample size and negative finding in TDT test, this study is the first report that there is positive association between the functional polymorphism of COMT gene the TD.

• Journal of the military operations research society of Korea
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• v.35 no.3
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• pp.17-30
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• 2009

In this study, we propose the operational availability computation model that can be used on the weapon system's requirement planning phase. The proposed model consists of the time parameters of Ao(Operational Availability) for a system and each time parameter's estimation method. The time parameters for Ao computation are TT(Total Time) and TDT(Total Down Time). The time parameters are defined by considering OMS/MP(Operational Mode Summary/Mission Profile) elements. TT is a calendar time as a specific mission time at wartime or one year at peacetime. TDT consists of TPM(Total Preventive Maintenance time), TCM (Total Corrective maintenance time), TALDT(Total Administrative and Logistics Down Time). Then the estimation method for these time parameters are presented by the weapon systems types.

• Korean Journal of Biological Psychiatry
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• v.16 no.1
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• pp.25-36
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• 2009

Objectives : The aim of this study was to investigate the association between Korean ADHD patients and the l/s polymorphism of serotonin transporter(5-HTTLPR). Methods : The study sample consisted of 189 Korean ADHD children diagnosed by Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version-Korean Version(K-SADS-PL), both parents of ADHD children, and 150 normal children. DNA were extracted from the blood of all samples, and genotyping was done. Based on the allele and genotype information, not only the case-control analysis between ADHD and normal children but also the family-based association test among ADHD children and their parents. Transmission disequilibrium test(TDT) were performed for family-based associated test(number of trio=113). The results of the clinical rating and neuropsychological tests were compared according to the l/s genotype of ADHD children. Results : In case-control analysis, there were no statistically significant difference of l/s gene polymorphism between ADHD and normal children in various kinds of analysis condition. In family-based association study, TDT failed to detect linkage disequilibrium between l/s gene polymorphism and ADHD in whole ADHD families. However, in the families of ADHD inattentive type only(number of trio=23), I allele was transmitted more preferentially in the proband with ADHD even if the number of families was small(${\chi}^2$=4.57, p=.032). In the analysis of the results from the clinical scales and neuropsychological tests in ADHD children, the score of the Novelty- Seeking of ADHD children with l/l genotype was significantly lower than with the other genotypes(F=3.15, p=.047), and that of Self Transcendence was significantly higher(F=4.25, p=.017). Conclusion : The results of this study suggest there were no significant genetic association between the 5- HTTLPR gene polymorphism and Korean ADHD.

• Food Science of Animal Resources
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• v.29 no.3
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• pp.310-316
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• 2009

In this study, the influence of pressure assisted mild thermal inactivation (PAMTI) on E. coli ATCC 10536 was examined at 200 MPa and temperature range of $20-50^{\circ}C$. Inactivation rate significantly increased (p<0.05) as temperature and time increased at 200 MPa. The maximum inactivation (7.91 log reduction) was obtained at $50^{\circ}C$ for 30 min under 200 MPa, which meant the complete inactivation of E. coli ATCC 10536. Inactivation kinetics were evaluated with the first order inactivation rate (k), activation energy ($E_a$), thermal death time (TDT), and z value. Kinetic parameters were significantly (p<0.05) influenced by variation temperature of PAMTI. In this study, the synergistic effect of pressure and temperature were found in the inactivation of E. coli ATCC 10536 through PAMTI.

• East Asian Journal of Business Economics (EAJBE)
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• v.5 no.3
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• pp.33-40
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• 2017

Purpose - This paper suggests approaching methods for a way of strategies for traditional market extend and new ebusiness, market development, and plan of new product in the future and develop a way of method for cooperation through analysis on the smart phone market trend in different culture, effectively. Research design, data, methodology - As research design, data, and methodology, this paper suggests new idea and approaches from comparing characteristics analysis of smart phone market in different culture in AEC. This paper takes data to analysis from ITU, World Bank, AEC, and IMF. These organizer's data can be trusted as official society in the world. This paper can prove market and the characteristics of society through the corresponding results. Results - This paper can suggest the novel idea on market development and the big possibility depend on ACE country and can describe the possibility on new market because of low smart phone market penetration and low digital market penetration. Conclusions - This paper concludes to develop e-business, culture friendly ship, linking with education, development of appropriate technology depend on country, and should develop new strategy for market extend to low penetration.