There are many rare variants in each individual. Establishing the significance of these variants in a particular environmental context, and dealing with the myr

There are many rare variants in each individual. Establishing the significance of these variants in a particular environmental context, and dealing with the myriad of potential interactions with other variants is probably not tractable with the experimental design you describe. High throughput phenotypic screens which test the cellular affects of inserting particular variants could help, as they would prune the number of potential variants, but the false negative rate is high. Genomic determinism may not exist in a useful sense in the current era.