If you have a cell that is producing a lot of a given protein (such as hemoglobin in erythrocytes) and you want to isolate the gene that transcribes the mRNA for that protein, the method that would likely give you the best results would be
I just can’t figure it out? Is there a way to go from protein to mRNA?
you will have degenerated sequence, because most of amino acids are coded by more than one triplet. But if you manage to select piece where are mostly AAs coded by only one or two codons, you could prepare degenerated probes and use them for the hybridization. However, that will not work for hemoglobin in erythrocytes.