ISSN:0741-0395    

DOI:10.1002/gepi.1370010102

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

年代:1984

数据来源: WILEY

ISSN:0741-0395    

DOI:10.1002/gepi.1370010103

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

年代:1984

数据来源: WILEY

摘要:

AbstractAn investigation of the genetic epidemiology of breast cancer involving complex segregation analysis of 200 breast cancer pedigrees of Danish extraction is presented. The observed distribution of breast cancer is compatible with transmission of an autosomal‐dominant gene with no evidence for residual family resemblance. The gene frequency of the abnormal allele is 0.00756, and the displacement between the homozygous genotype means is 1.695. The gene frequency accounts for a significant proportion of breast cancer in young women, whereas by an advanced age a majority (87%) of affected women are phenocopies. Genetic modeling of other breast cancer families and results of linkage studies are reviewe

ISSN:0741-0395    

DOI:10.1002/gepi.1370010104

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

年代:1984

数据来源: WILEY

摘要:

AbstractThis paper describes a general genetic model which encompasses both autosomal and X‐linked inheritance as submodels. It allows one to test for X‐linked inheritance of a trait by comparing the likelihood of X‐linked inheritance to the likelihood of the general genetic model. The general model is formulated as two loci, the first representing the trait locus and the second representing the sex chromosomes. The test for X‐linked inheritance is a test of linkage between the two loci. Three data sets were analyzed using this approach. Each was also analyzed using a variant of a model introduced by Demenais and Elston [1981], which treats the transmission probabilities as estimable parameters. Similar conclusions were reached using eithe

ISSN:0741-0395    

DOI:10.1002/gepi.1370010105

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

年代:1984

数据来源: WILEY

摘要:

AbstractSegregation analysis favors a gene additive on liability with a frequency of 0.022, which is nearly recessive on the penetrance scale. Less than one‐eighth of DR3 and DR7 haplotypes carry a determinant for coeliac disease. There is significant excess of DR3/7 heterozygotes among patients, indicating that the determinants are qualitatively different in DR3 and DR7 haplotypes. Linkage to HLA is highly significant (maximum lod score = 10.9). Evidence for recombination of 8% in males is attributed to residual errors in the model. We suggest an approach to a more precise mode

ISSN:0741-0395    

DOI:10.1002/gepi.1370010106

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

年代:1984

数据来源: WILEY

摘要:

AbstractComplex segregation analysis under the unified mixed model of inheritance (major gene and multifactorial) is performed on families ascertained through 23 probands with hypoalphalipoproteinemia (depressed HDL‐cholesterol, denoted HDL‐c). Evidence for segregation of a recessive major gene for depressed HDL‐c with frequency q = 0.116, in addition to multifactorial transmission (H = 0.572), is found in these families. Reanalysis of a subset of families with severely depressed HDL‐c confirms the conclusions based on the original analysis, except that different definitions of “affection” give rise to different estimates of gene frequency. Our finding of a recessive mode of inheritance differs from previous claims for a dominant gene because previous analyses did not use a mixed model for segregation analysis of hypoalphalipoproteinemia. When the significant multifactorial background is neglected, we also find evidence for the invalid claim of a dominant gene. This demonstrates the necessity of using mixed models for determining the mode of inheritance of a give

ISSN:0741-0395    

DOI:10.1002/gepi.1370010107

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

年代:1984

数据来源: WILEY

摘要:

AbstractAlthough only a small proportion of common cancers show familial aggregation, studying such families can elucidate the roles of shared environment and genes in the development of neoplasia. We report an analysis of nine colon cancer pedigrees using new nonparametric objective methods to measure familial aggregation as a means of determining the existence of heterogeneity in the data. Each family was selected through a proband with nonpolyposis colon cancer who had a first‐degree relative with documented colon cancer. To assess the aggregation of different cancers in these families we employ a method which evaluates both excess number of cases as well as distribution by risk in family members. We find that eight of the nine families exhibit significant aggregation of colon cancer: endometrial cancer aggregates in three families, breast in none, kidney in one, and all sites in eight. In this way, we show that two families fit the criteria for Cancer Family Syndrome, and that one is not a high‐risk cancer fam

ISSN:0741-0395    

DOI:10.1002/gepi.1370010108

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

年代:1984

数据来源: WILEY

摘要:

AbstractAlcohol consumption, anxiety, and depression were measured by questionnaire in 572 twin families ascertained from the Institute of Psychiatry (London) normal twin register, each family consisting of an adult twin pair, their parents, and siblings‐a total of 1,742 individuals. A multivariate normal model for pedigree analysis was applied to each variable, with power transformations fitted to maximise the fit with distributional assumptions. The effect of shared twin environment was estimated by considering the measured cohabitation history of twin pairs. For log‐transformed alcohol consumption, amongst current drinkers this effect was the same for MZ and DZ pairs but depended on the cohabitation status of pairs. For both anxiety and depression the effect was clearly not the same for MZ and DZ pairs. Therefore the basic assumption of the classical twin method appears to be invalid for all three traits. Estimates of heritability derived from these analyses were compared with those obtained (1) by applying the classical twin method to twin data only, and (2) by a pedigree analysis ignoring the effect of shared twin environment. For all variables there were considerable differences between estimates based on the three models. This study illustrates that data from twins and their relatives which includes information on cohabitation history might distinguish shared genes and shared environment as causes of familial aggregation. In these behavioral traits the effect of shared twin environment may depend on zygosity and play a major role in explaining familial aggregation in twin family d

ISSN:0741-0395    

DOI:10.1002/gepi.1370010109

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

年代:1984

数据来源: WILEY

摘要:

AbstractThe recent finding of a closely linked DNA marker to the Huntington Disease gene allows the opportunity for prenatal and preclinical diagnosis. The methodology for using these markers for prediction in late age of onset disorders is discussed. Since these methods are both difficult and complex for the majority of genetic counselors, a simple solution is suggested. This involves using the well known linkage program LIPED and running it twice for a given consultand, once assuming he carries the gene and once that he is homozygous normal. This will allow accurate predictions for counselors with limited backgrounds in pedigree analysis.

ISSN:0741-0395    

DOI:10.1002/gepi.1370010110

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

年代:1984

数据来源: WILEY

ISSN:0741-0395    

DOI:10.1002/gepi.1370010101

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

年代:1984

数据来源: WILEY