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You are a researcher at for a wheat breeding company and, after screening thousands of lines, have found one line that is tolerant to a new herbicide. Assuming that a single gene causes this phenotype, explain how one could determine the gene sequence using map-based cloning techniques. (that is, you do not know anything about the sequence of the DNA). You do have a plant line that is susceptible and the newly identified line is resistant (tolerant) ( assume starting out both are homozygous for the gene), and you also have a number of DNA markers at your disposal.
Identify and explain the steps you have to take to identify the DNA sequence that causes the resistance.
To help you out, start by thinking what else you need, for example, do you have to cross the lines? Do you need genetic maps/tools? Do you need to make a library?