ESTIMATION OF GENETIC COVARIANCE FROM JOINT OFFSPRING-PARENT AND SIB-SIB STATISTICS

Estimation of genetic covariance from joint offspring-parent and sib-sib statistics.

Formulae for calculating the variances and covariances of estimates of genetic variance or covariance from offspring-parent and sib covariance data are presented. The model consists of a one-way classification of families with unequal numbers of offspring, where normally distributed traits x (a parental measure), y and z (offspring measures) are recorded. Procedures for pooling offspring-parent...

Parent-Offspring and Full Sib Correlations under a Parent-Offspring Mating System.

Biased estimation of the recombination fraction using half-sib families and informative offspring.

A maximum-likelihood method to estimate the recombination fraction and its sampling variance using informative and noninformative half-sib offspring is derived. Estimates of the recombination fraction are biased up to 20 cM when noninformative offspring are discarded. In certain scenarios, the sampling variance can be increased or reduced up to fivefold due to the bias in estimating the recombi...

Comparison of Affected-Sib-Pair Statistics for Multi-Locus Genetic Disease Models in Multi-Marker Analysis

Now, many human genetist are trying to detect agent loci of common diseases, such as hypertension, diabetes, heart disease, multiple sclerosis, arthritis, obesity, and so on. These diseases are caused by multiple genes interacting with each other and with environmental factors to create a gradient of genetic susceptibility to disease. Even when a trait is governed by multiple disease genes, for...

Maximum likelihood estimation of linkage disequilibrium in half-sib families.

Maximum likelihood methods for the estimation of linkage disequilibrium between biallelic DNA-markers in half-sib families (half-sib method) are developed for single and multifamily situations. Monte Carlo computer simulations were carried out for a variety of scenarios regarding sire genotypes, linkage disequilibrium, recombination fraction, family size, and number of families. A double hetero...