@misc{GaertnerSteinfathAndorfetal.2009,
  author    = {G{\"a}rtner, Tanja and Steinfath, Matthias and Andorf, Sandra and Lisec, Jan and Meyer, Rhonda C. and Altmann, Thomas and Willmitzer, Lothar and Selbig, Joachim},
  title     = {Improved heterosis prediction by combining information on DNA- and metabolic markers},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-45132},
  year      = {2009},
  abstract  = {Background: Hybrids represent a cornerstone in the success story of breeding programs. The fundamental principle underlying this success is the phenomenon of hybrid vigour, or heterosis. It describes an advantage of the offspring as compared to the two parental lines with respect to parameters such as growth and resistance against abiotic or biotic stress. Dominance, overdominance or epistasis based models are commonly used explanations. Conclusion/Significance: The heterosis level is clearly a function of the combination of the parents used for offspring production. This results in a major challenge for plant breeders, as usually several thousand combinations of parents have to be tested for identifying the best combinations. Thus, any approach to reliably predict heterosis levels based on properties of the parental lines would be highly beneficial for plant breeding. Methodology/Principal Findings: Recently, genetic data have been used to predict heterosis. Here we show that a combination of parental genetic and metabolic markers, identified via feature selection and minimum-description-length based regression methods, significantly improves the prediction of biomass heterosis in resulting offspring. These findings will help furthering our understanding of the molecular basis of heterosis, revealing, for instance, the presence of nonlinear genotype-phenotype relationships. In addition, we describe a possible approach for accelerated selection in plant breeding.},
  language  = {en}
}
@misc{SteinfathGaertnerLisecetal.2009,
  author    = {Steinfath, Matthias and G{\"a}rtner, Tanja and Lisec, Jan and Meyer, Rhonda C. and Altmann, Thomas and Willmitzer, Lothar and Selbig, Joachim},
  title     = {Prediction of hybrid biomass in Arabidopsis thaliana by selected parental SNP and metabolic markers},
  series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {1324},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-43111},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-431115},
  pages     = {9},
  year      = {2009},
  abstract  = {A recombinant inbred line (RIL) population, derived from two Arabidopsis thaliana accessions, and the corresponding testcrosses with these two original accessions were used for the development and validation of machine learning models to predict the biomass of hybrids. Genetic and metabolic information of the RILs served as predictors. Feature selection reduced the number of variables (genetic and metabolic markers) in the models by more than 80\% without impairing the predictive power. Thus, potential biomarkers have been revealed. Metabolites were shown to bear information on inherited macroscopic phenotypes. This proof of concept could be interesting for breeders. The example population exhibits substantial mid-parent biomass heterosis. The results of feature selection could therefore be used to shed light on the origin of heterosis. In this respect, mainly dominance effects were detected.},
  language  = {en}
}
@article{LisecSteinfathMeyeretal.2009,
  author    = {Lisec, Jan and Steinfath, Matthias and Meyer, Rhonda C. and Selbig, Joachim and Melchinger, Albrecht E. and Willmitzer, Lothar and Altmann, Thomas},
  title     = {Identification of heterotic metabolite QTL in Arabidopsis thaliana RIL and IL populations},
  issn      = {0960-7412},
  doi       = {10.1111/j.1365-313X.2009.03910.x},
  year      = {2009},
  abstract  = {Two mapping populations of a cross between the Arabidopsis thaliana accessions Col-0 and C24 were cultivated and analyzed with respect to the levels of 181 metabolites to elucidate the biological phenomenon of heterosis at the metabolic level. The relative mid-parent heterosis in the F-1 hybrids was <20\% for most metabolic traits. The first mapping population consisting of 369 recombinant inbred lines (RILs) and their test cross progeny with both parents allowed us to determine the position and effect of 147 quantitative trait loci (QTL) for metabolite absolute mid-parent heterosis (aMPH). Furthermore, we identified 153 and 83 QTL for augmented additive (Z(1)) and dominance effects (Z(2)), respectively. We identified putative candidate genes for these QTL using the ARACYC database (http://www.arabidopsis.org/ biocyc), and calculated the average degree of dominance, which was within the dominance and over-dominance range for most metabolites. Analyzing a second population of 41 introgression lines (ILs) and their test crosses with the recurrent parent, we identified 634 significant differences in metabolite levels. Nine per cent of these effects were classified as over-dominant, according to the mode of inheritance. A comparison of both approaches suggested epistasis as a major contributor to metabolite heterosis in Arabidopsis. A linear combination of metabolite levels was shown to significantly correlate with biomass heterosis (r = 0.62).},
  language  = {en}
}