摘要:

AbstractApolipoproteins are the protein constituents of lipoproteins, the particles that transport cholesterol and triglycerides in the plasma. Numerous epidemiologic studies have associated variations in plasma levels of lipoproteins and apolipoproteins with the development of atherosclerosis. Furthermore, genetic variations in lipoproteins and apolipoproteins have been associated with disorders of lipid metabolism. Recent advances in biochemical and molecular genetic methods have resulted in an increased understanding of interindividual variations in lipoprotein metabolism and of their relationship to atherosclerosis and the dyslipoproteinemias. In particular, certain DNA restriction fragment length polymorphisms of the apolipoprotein genes have, in the last few years, been associated with atherosclerotic diseases and dyslipoproteinemias. We believe that genetic markers, when used in conjunction with traditional clinical and biochemical determinations, may one day be useful in predicting atherosclerosis susceptibility in the general population.

ISSN:0741-0395    

DOI:10.1002/gepi.1370040302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe first portion of this communication reiterates the method of discarding single probands for studying the segregation ratio under incomplete ascertainment. The organization of the algebra leads to the second portion, in which the “self‐contained” subsets are constructed with respect to both the segregation ratio and the ascertainment ratio. These subsets make a more detailed study of segregation and ascertainment pos

ISSN:0741-0395    

DOI:10.1002/gepi.1370040303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA statistical model that uses an iterative maximum likelihood estimation procedure is proposed for measuring and testing the association between polymorhphic genetic markers and quantitative traits in human pedigrees, after adjusting for covariates such as age and sex. The model allows the quantitative trait to have a familial correlation structure among the individuals in the sample and to follow one of a broad class of skewed or kurtotic underlying distributions. The use of the model is illustrated, and the results are compared to those using models that assume normality without any transformation and do not incorporate familial correlations.

ISSN:0741-0395    

DOI:10.1002/gepi.1370040304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA robust approach for estimating standard errors of variance components by using quantitative phenotypes from families ascertained through a proband with an extreme phenotypic value is presented. Estimators that use the multivariate normal distribution as a “working likelihood” are obtained by computing conditional In‐likelihoods, conditional first and second derivatives in a Newton‐Raphson approach. Robust estimates of standard errors about the estimators are also provided. Tests of hypotheses are based on a modification of the score test, which allows the assumption of multivariate normality to be relaxed. Conditional goodness‐of‐fit statistics are proposed that can be used to examine the fit of separate pedigrees to the overall model. This robust approach for estimating the standard errors for variance components by conditioning on the proband's phenotype will allow general inferences to be made from the analysis of families ascertained through probands with extreme or unusual phenotypes and should be most appropriate for studying many physiological traits that may be intrinsicall

ISSN:0741-0395    

DOI:10.1002/gepi.1370040305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThree spirometric measures of pulmonary function were used to estimate genetic and nongenetic components of variance for 781 members of 158 families ascertained through a proband with obstructive pulmonary disease. Forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), and the ratio of these two (FEV1/FVC) were adjusted for age, sex, race, smoking, and height and used in a robust approach to estimate variance components after conditioning on the proband's observed value. The best fitting model for both residual FEV1/FVC and FEV1included an additive genetic component representing 25% and 9% of the variation in these two traits, respectively. In addition, there was a significant correlation between parents in residual FEV1/FVC, and a component shared among full sibs was statistically significant for residual FEV1. No evidence of a genetic component for residual FVC was found in this analysis. Although these results agree with previous reports based on other populations in showing a substantial degree of direct genetic control over spirometric measures of pulmonary function, they also raise the possibility of etiologic heterogeneity.

ISSN:0741-0395    

DOI:10.1002/gepi.1370040306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractPopulation dynamics of two alleles, A1and A2, at a locus under social selection have been studied by considering incomplete penetrance of the three genotypes. A social selection model is constructed by assuming that the fitness of an individual is determined by his or her own phenotype as well as parental phenotypes. For both multiplicative and additive fitness models, sufficient conditions for a protected polymorphism depend on the reduced fitness of affected individuals (γ), the reduced fitness of all individuals resulting from affected parents (β), and the penetrance probabilities,f1,f2, andf3, for the three genotypes, A1A1, A1A2, and A2A2. These conditions reduce to two biologically important cases: 1)f1f3and βf2− γ/(1 − γ), and the most common form of the equilibrium frequency of the allele A2is given by (f1

ISSN:0741-0395    

DOI:10.1002/gepi.1370040307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0741-0395    

DOI:10.1002/gepi.1370040301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY