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A parametric copula model for analysis of familial binary data

Article Abstract:

A parametric copula model has been developed for analysis of familial binary data. A class of copula models can be used for the analysis of exchangeable categorical data. The class of copula models can be incorporated into a familial framework. The joint distribution of binary outcomes is characterized by a function of the given marginals and the function is called a copula. The copula depends on an aggregation parameter weakly dependent on the marginal distributions. It has been proposed that a nuclear family be separated into two sets of equicorrelated data, parents and offspring, each characterized by an aggregation parameter. Marginal probabilities would be modeled through logistic representation. The advantage of the model is provision of estimates of the aggregation parameters independent of family size. It does not require any arbitrary ordering of sibs, also an advantage. The model has been applied to a combined segregation-lineage analysis of levels of plasma angiotensin I.

France, Usage, Mathematical models, Family, Quantitative genetics

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Immunoglobulin class switch recombination: will genetics provide new clues to mechanism?

Article Abstract:

Genetics research may give clues about the mechanism of immunoglobulin class switch recombination. Programmed changes in genomic structure are necessary for development of the immune system. Three processes, somatic hypermutation, class-switch recombination, and V(D)J recombination, set up and fine tune immunoglobulin genes as the immune system develops and deals with foreign antigens. These processes are discussed.

United States, Research, Physiological aspects, DNA repair, Genetic recombination, Immunodeficiency, Antibody diversity

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