I agree with the above. Pl. refer to texts on gene mapping technology and related literature. In Practical Breeding methodology , cross resistant strains with susceptible ones to study the outcome in the filials and take further approaches to develop completely resistant strains. This is time consuming, but worth attempting. Investigations to be carried out in secluded and closed labs. with strict quarantine precautions.
I agree with Haifa Juma. you can think of which samples you are going to use such as blood or tissues. Then you don't want to use the Genome wide ; yo can use microaarray for gene expression