## Abstract Allison ([1997] Am. J. Hum. Genet. 60:676–690) proposed four versions of the transmission‐disequilibrium test (TDT) for quantitative traits when there is __extreme‐threshold sampling__, i.e., the trios having an offspring trait value between a priori defined thresholds are excluded from
Power of transmission/disequilibrium tests in admixed populations
✍ Scribed by Miao-Xin Li; Lin Jiang; You-Qiang Song; Pak C. Sham
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 215 KB
- Volume
- 32
- Category
- Article
- ISSN
- 0741-0395
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✦ Synopsis
Abstract
The power of transmission/disequilibrium tests (TDTs) for detecting disease susceptibility loci is expected to be influenced by population admixture through its impact on the degree of linkage disequilibrium (LD) between the genetic marker and the DSL. However, few studies have been done to systematically examine this behavior of the TDTs in admixed populations. In the present study, extensive computer simulations were conducted to explore how population admixture affects the power of TDTs. It was found that (1) in newly admixed populations, the LD due to admixture makes no contribution to the power of TDTs, and it is the averaged background LD in the parental populations that determines the power of TDTs; but (2) after random mating between the admixed populations, the LD due to admixture becomes effective in increasing or decreasing the power of the tests, and (3) incomplete random mating can prolong the time for the LD due to admixture to become effective. This study clarifies the potential influence of population admixture on the performance of TDTs. Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.
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