Thesis (Ph. D)

Recent progress in molecular genetics has made it possible for scientists to gain a fine scale genetic map of various organisms. Such improvements in molecular genetics have been attained by placing genetic markers (RFLPs, isozymes, RAPDs) along a genome of interest. It is through these markers that an initial framework for inferences about quantitative trait loci (QTL) can be built. Quantitative traits are largely affected by an association of many genes, therefore the location which involves these quantitative traits cannot be described simply in the context of a typical genetic map scenario. Instead, a statistical representation of the quantitative trait serves to tell us how much of the genetic variation in the parental lines is contributed to the offspring by each region that is identified through genetic markers in the progeny. Statistical issues leading up to and including the search and location of quantitative trait loci are investigated. A preliminary method for ordering molecular markers is presented with the purpose of providing the fundamental structure involved in the search for QTL. In developing this method, issues of genetic maps, recombination, and assumptions of the mating scheme are investigated. The statistical theory supporting single marker and interval mapping methods for detecting and locating QTL is explored for the purpose of evaluating the robustness of these procedures. Lastly, a new method for detecting and locating QTL is described. Once QTL have been identified as being contained within a specific region of DNA this will allow for eventual molecular cloning and characterization of genes involved in quantitative inheritance.

English

Thesis Collection