• Asian-Australasian Journal of Animal Sciences
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• 제29권12호
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• pp.1682-1687
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• 2016

The objective of this study was to estimate the genetic parameters of milk protein yields in Iranian Holstein dairy cattle. A total of 1,112,082 test-day milk protein yield records of 167,269 first lactation Holstein cows, calved from 1990 to 2010, were analyzed. Estimates of the variance components, heritability, and genetic correlations for milk protein yields were obtained using a random regression test-day model. Milking times, herd, age of recording, year, and month of recording were included as fixed effects in the model. Additive genetic and permanent environmental random effects for the lactation curve were taken into account by applying orthogonal Legendre polynomials of the fourth order in the model. The lowest and highest additive genetic variances were estimated at the beginning and end of lactation, respectively. Permanent environmental variance was higher at both extremes. Residual variance was lowest at the middle of the lactation and contrarily, heritability increased during this period. Maximum heritability was found during the 12th lactation stage ($0.213{\pm}0.007$). Genetic, permanent, and phenotypic correlations among test-days decreased as the interval between consecutive test-days increased. A relatively large data set was used in this study; therefore, the estimated (co)variance components for random regression coefficients could be used for national genetic evaluation of dairy cattle in Iran.

• Asian-Australasian Journal of Animal Sciences
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• 제24권8호
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• pp.1031-1040
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• 2011

The objective of this study was to characterize factors influencing genetic improvement of dairy cattle for milk production at farm level. Data were accumulated from 305-day milk yields and pedigree information from 1,921 first-lactation dairy cows that calved from 1990 to 2007 on 161 farms in Central Thailand. Variance components were estimated using average information restricted maximum likelihood procedures. Animal breeding values were predicted by an animal model that contained herd-year-season, calving age, and regression additive genetic group as fixed effects, and cow and residual as random effects. Estimated breeding values from cows that calved in a particular month were used to estimate genetic trends for each individual farm. Within-farm genetic trends (b, regression coefficient of farm milk production per month) were used to classify farms into 3 groups: i) farms with negative genetic trend (b<-0.5 kg/mo), ii) farms with no genetic trend (-0.5 kg/$mo{\leq}b{\leq}0.5$ kg/mo), and iii) farms with positive genetic trend (b>0.5 kg/mo). Questionnaires were used to gather information from individual farmers on educational background, herd characteristics, farm management, decision making practices, and opinion on dairy farming. Farmer's responses to the questionnaire were used to test the association between these factors and farm groups using Fisher's exact test. Estimated genetic trend for the complete population was $0.29{\pm}1.02$ kg/year for cows. At farm level, most farms (40%) had positive genetic trend ($0.63{\pm}4.67$ to $230.79{\pm}166.63$ kg/mo) followed by farms with negative genetic trend (35%; $-173.68{\pm}39.63$ to $-0.62{\pm}2.57$ kg/mo) and those with no genetic trend (25%; $-0.52{\pm}3.52$ to $0.55{\pm}2.68$ kg/mo). Except for educational background (p<0.05), all other factors were not significantly associated with farm group.

• 한국콘텐츠학회논문지
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• 제18권2호
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• pp.47-56
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• 2018

본 연구는 국내 외의 종양유전간호 관련 연구를 분석하여 연구동향을 파악하고자 하였다. 종양유전간호 관련 주제로 학술지에 게재된 논문들의 초록에서 제시한 핵심어들을 중심으로 한 텍스트 네트워크 분석을 실시하였다. 핵심어이자 중심성이 높은 주제어로 Nurse, Cancer, Genetic, Patient, Knowledge, Care, Genetic Test 등이 확인되었으며, 시기별 연구동향을 확인한 결과, 2003년 이후 Information, Care, Knowledge 등의 주제어를 포함한 연구들이 증가하였다. 간호학의 메타 패러다임으로 주제어를 분류한 결과, 건강, 간호, 인간, 환경 순으로 중심성이 높게 나타났다. 건강 영역 중 건강 위험 범주에서 Genetics, Risk, 건강 증진 범주에서 Genetic Test, Prevention 등이 가장 높은 빈도로 나타났다. 본 연구를 통해 종양유전간호 연구의 동향을 파악할 수 있으며, 유전성 암 환자들을 위한 간호 중재에 주축이 되는 간호사의 역할 및 중재프로그램 개발의 방향 설정에 활용될 수 있다는 점에서 의미가 있다.

• Communications for Statistical Applications and Methods
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• 제24권6호
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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.

• Genomics & Informatics
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• 제8권3호
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• pp.142-149
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• 2010

In recent years, genome-wide association (GWA) studies have successfully led to many discoveries of genetic variants affecting common complex traits, including height, blood pressure, and diabetes. Although GWA studies have made much progress in finding single nucleotide polymorphisms (SNPs) associated with many complex traits, such SNPs have been shown to explain only a very small proportion of the underlying genetic variance of complex traits. This is partly due to that fact that most current GWA studies have relied on single-marker approaches that identify single genetic factors individually and have limitations in considering the joint effects of multiple genetic factors on complex traits. Joint identification of multiple genetic factors would be more powerful and provide a better prediction of complex traits, since it utilizes combined information across variants. Recently, a new statistical method for joint identification of genetic variants for common complex traits via the elastic-net regularization method was proposed. In this study, we applied this joint identification approach to a large-scale GWA dataset (i.e., 8842 samples and 327,872 SNPs) in order to identify genetic variants of obesity for the Korean population. In addition, in order to test for the biological significance of the jointly identified SNPs, gene ontology and pathway enrichment analyses were further conducted.

• Communications for Statistical Applications and Methods
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• 제17권5호
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• pp.733-743
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• 2010

가족기반 유전연구에서 단일염기다형성(SNP) 및 일배체형(haplotype)을 이용한 질병-유전자간 연관성 분석은 주요 관심부분 중 하나이다. 이진형질인 경우 사용되는 고전적인 TDT(transmission/disequilibrium test)는 부/모/자의 유전정보를 모두 알 수 있을 때에 쓸 수 있다. 그러나 경우에 따라서는 부모의 유전자형에 대한 정보를 사용할 수 없을 수가 있는데, 치매등과 같이 늦게 발병하는 질환에서 이런 경우가 자주 발생한다. 부모의 유전자형을 모를 때 이를 대체할 수 있는 방법으로 형매(sib)의 유전정보를 이용하는 방법이 있다. 본고에서는 가족기반연구에서 형매의 유전정보를 이용하는 분석방법에 대해 고찰하고 모의실험을 통해 이들의 검정력을 비교하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1231-1236
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• 2005

Genetic parameters for first lactation milk production based on test day (TD) records of 56319 Iranian Holstein cows from 655 herds that first calved between 1991 and 2001 were estimated with restricted maximum likelihood method under an Animal model. Traits analyzed were milk yield and milk fat percentage. Heritability for TD records were highest in second half of the lactation, ranging from 0.11 to 0.19 for milk yield and 0.038 to 0.094 for milk fat percentage respectively. Estimates for lactation records for these traits were 0.24 and 0.26 respectively. Genetic correlations between individual TD records were high for consecutive TD records (>0.9) and decreased as the interval between tests increased. Estimates of genetic correlations of TD yield with corresponding lactation yield were highest (0.78 to 0.86) for mid-lactation (TD3 to TD8). Phenotypic correlations were lower than corresponding genetic correlations, but both followed the same pattern. For milk fat percentage no clear pattern was found. Results of this study suggested that TD yields especially in mid-lactation may be used for genetic evaluation instead of 305-day yield.

• 보험의학회지
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• 제21권
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• pp.121-139
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• 2002

• 대한본초학회지
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• 제20권2호
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• pp.1-6
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• 2005

Objectives : The purpose of this study is to investigate genetic toxicity of Cervi pantotrichum Cornu herbal acupuncture solution(CPCHA). Methods : In this study, a series of investigation have been carried out to analyze the effects of Cervi pantotrichum Cornu herball acupuncture solution(CPCHA) on colony forming ability of NIH3T3cells, Hela cells and adrenorectal coloncell for genetic toxicity test. Results and Conclusions : From the above results, it is suggested that Cervi pantotrichum Cornu herball acupuncture solution(CPCHA) was limited 0.5-10ug/ml by test. Cervi pantotrichum Cornu herball acupuncture solution(CPCHA) did not exert the protective role to the genetic toxicity in kinds of cell lines used in this study. From these results, Cervi pantotrichum Cornu herbal aqua-acupuncture solution needs further study to prove it's function in cell culture system.

• Asian-Australasian Journal of Animal Sciences
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• 제15권3호
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• pp.315-320
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• 2002

Test-day records (n=13677) sampled from 896 ewes in 5-9 (${\mu}$=7.5) monthly test-days were used to estimate genetic and phenotypic parameters of test-day yields, lactation milk yield (TMY), length of the milking period (DAYS) and three measures of persistency of milk yield in Boutsico dairy sheep. Τhe measures of persistency were the slope of the regression line (${\beta}$), the coefficient of variation (CV) of the test-day milk yields and the maximum to average daily milk yield ratio (MA). The estimates of variance components were obtained under a linear mixed model by restricted maximum likelihood. The heritability of test-day yields ranged from 0.15 to 0.24. DAYS were found to be heritable ($h^2$=0.11). Heritability estimates of ${\beta}$, CV and MA were 0.15, 0.13, 0.10, respectively. Selection for maximum lactation yields is expected to result in prolonged milking periods, high rates of decline of yields after peak production, variable test-day yields and higher litter sizes. Selection for flatter lactation curves would reduce lactation yields, increase slightly the length of the milking period and decrease yield variation as well as litter size. The most accurate prediction of TMY was obtained with a linear regression model with the first five test-day records.