Submitted to: Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/15/2007
Publication Date: 1/15/2008
Citation: Buckler Iv, E.S., Yu, J., Holland, J.B., Mcmullen, M.D. 2008. Genome-wide complex trait dissection through nested association mapping. Genetics. 178:539-551. Interpretive Summary: Most genetic mapping has either involved examining the offspring of two individuals (linkage mapping) or examining a large collection of unrelated individuals (association mapping). We describe a way to combine the strengths of both approaches in Nested Association Mapping (NAM). Then using real and simulated data demonstrate the statistical and genetic power of the approach. Nested Association Mapping is now being first implemented in maize. It will allow numerous of traits to be dissected down to the gene level for first time. In conjunction the ongoing maize genome sequence, nested association mapping will no doubt prove instrumental in identifying and describing the genes and alleles that control complex traits.
Technical Abstract: We investigated the genetic and statistical properties of the nested association mapping (NAM) design currently being implemented in maize (26 diverse founders and 5000 distinct immortal genotypes), which simultaneously exploits the advantages of both linkage analysis and association mapping. We demonstrated the power of NAM as a high-resolution cost-effective genome scan through computer simulations based on empirical marker data and simulated traits with different complexities. With high density common-parent-specific (CPS) markers genotyped for the founders and the progenies, the inheritance of chromosome segments nested within two adjacent CPS markers was inferred through linkage. Genotyping the founders with additional high-density markers enabled the projection of genome information, capturing linkage disequilibrium information, from founders to progenies. With 5000 genotypes, 30% to 79% of the simulated quantitative trait loci (QTL) were precisely identified at the gene level. This new complex trait dissection strategy should greatly facilitate endeavors to link molecular variation with phenotypic variation for various complex traits.