## Abstract An improved sibβpair test for linkage is introduced which is superior to the previously proposed tests. The test is derived from the standard chiβsquared goodness of fit statistic by restricting the alternative hypothesis to the genetically possible. Critical values are given and exact
Sib-pair linkage tests for disease susceptibility loci: Common tests vs. the asymptotically most powerful test
β Scribed by Daniel J. Schaid; Todd G. Nick; D. C. Rao
- Publisher
- John Wiley and Sons
- Year
- 1990
- Tongue
- English
- Weight
- 597 KB
- Volume
- 7
- Category
- Article
- ISSN
- 0741-0395
No coin nor oath required. For personal study only.
β¦ Synopsis
Several statistical tests for linkage between a disease susceptibility locus and a marker locus for sib-pair data are examined analytically. Two common statistics, a test based on the mean number of marker alleles shared identical by descent by sib-pairs, and a test based on the proportion of sib-pairs sharing exactly two marker alleles, are shown to be special cases of a more general statistic. We use this more general statistic to derive the asymptotically most powerful statistic for a given genetic alternative hypothesis, and then compare this statistic with the "mean" statistic and the "proportion" statistic. Results indicate that the "mean" statistic generally compares well with the most powerful statistic. However, in some instances the "mean" statistic may lose power, relative to the most powerful. To guard against this, a new statistic (the maximum of the "mean" and "proportions" statistics) is considered and its asymptotic distribution is derived. Results indicate that this new statistic performs well.
π SIMILAR VOLUMES
An analytical study is conducted of the properties of statistical tests to detect linkage between a disease locus and a very polymorphic marker locus when data on sib pairs are available. In most instances the most powerful test is the test based on the mean number of marker alleles shared identical
Nick examines the problem of testing for linkage between a disease susceptibility locus and a marker locus for sib-pair data. Given a specified simple alternative for the parameters (pO, p I , p 2 ) of the multinomial distribution of (NO, N , , N2), where Nj denotes the number of sibs sharing exactl
Linkage analyses and association studies were employed to detect disease susceptibility loci leading to elevated Q1 levels in Problem 2B. Phenotypes were defined to be the dichotomous affection status, the quantitative value for Q1, and Q1 adjusted for covariates. The method of mod-scores (for the d
## Abstract Despite the numerous and successful applications of genomeβwide association studies (GWASs), there has been a lot of difficulty in discovering disease susceptibility loci (DSLs). This is due to the fact that the GWAS approach is an indirect mapping technique, often identifying markers.