Variance component methods are now being used in linkage analysis to detect genes influencing complex diseases. These methods are easily extended to allow for simultaneous estimation of both the additive effects of multiple loci on phenotypic variation (conditional oligogenic analysis) and the addit
Prior segregation analysis and the power to detect linkage
โ Scribed by Larry D. Atwood; Susan H. Slifer
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 52 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0741-0395
No coin nor oath required. For personal study only.
โฆ Synopsis
Complex parametric segregation and linkage analysis was performed on the simulated quantitative trait Q1 for all 200 replicates of the nuclear families data set. The segregation analysis inferred a major gene in 46% of the replicates. Among all replicates, including those that rejected a major gene, the power to detect suggestive linkage to any of three loci affecting Q1 was 0.600 and the false positive rate was 0.002. Among the replicates where a major gene was found, the power to detect suggestive linkage was 0.652 and the false positive rate was also 0.002. Thus, for purposes of linkage to this complex trait, a prior segregation then linkage analysis approach located a gene in 30% of all replicates, whereas a linkage only approach located a gene in 60% of all replicates.
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