Mapping genome-wide QTL of ratio traits with Bayesian shrinkage analysis for its component traits
The ratio trait is defined as a ratio of two regular quantitative traits with normal distribution, which is distinguished from regular quantitative traits in the genetic analysis because it does not follow the normal distribution. On the basis of maximum likelihood method that uses a special linear combination of the two component traits, we develop a Bayesian mapping strategy for ratio traits, which firstly analyzes the two component traits by Bayesian shrinkage method, and then generates a new posterior sample of genetic effects for a ratio trait from ones of population means and genetic effects for the two component traits, finally, infers QTL for the ratio trait via post MCMC analysis for the new posterior sample. A simulation study demonstrates that the new method has higher detecting power of the QTL than maximum likelihood method. An application is illustrated to map genome-wide QTL for relative growth rate of height on soybean.
KeywordsRatio trait QTL Bayesian shrinkage Relative growth rate
The research was supported by the Chinese National Natural Science Foundation Grant 30972077 to RY.
- Gunsett FC (1984) Linear index selection to improve traits defined as ratios. J Anim Sci 59:1185–1193Google Scholar
- Gunsett FC (1987) Merit of utilizing the heritability of a ratio to predict genetic change of a ratio. J Anim Sci 65:936–942Google Scholar
- Jin C, Fine JP, Yandell BS (2007) A unified semiparametric framework for quantitative trait loci analyses, with application to Spike phenotypes. JASA 477:56–67Google Scholar
- Kendall M, Stuart A (1979) The advanced theory of statistics, 4th edn. Griffin, LondonGoogle Scholar
- Satagopan JM, Yandell BS (1996) Estimating the number of quantitative trait loci via Bayesian model determination. Special contributed paper session on genetic analysis of quantitative traits and complex diseases, biometrics section, joint Statistical meetings. Chicago, ILGoogle Scholar
- Sun D, Li W, Zhang Z, Cheng Q, Yang Q (2006) Analysis of QTL for plant height at different developmental stages in soybean. Acta Agronomica Sinica 4:509–514Google Scholar
- Tsarouhas V, Gullberg U, Lagercrantz U (2002) An AFLP and RFLP linkage map and quantitative trait locus (QTL) analysis of growth traits in Salix. Theor Appl Genet 2–3:277–288Google Scholar
- Zhang YM, Xu S (2005) Advanced statistical methods for detecting multiple quantitative trait loci. Recent Res Devel Genet Breed 2:1–23Google Scholar