So, I have a goal to find a mutation of a gene which occur in the promoter region. The SNP is already well known so I imagine my workflow is to check the SNP and then compare it to the known mutation. The problem is, I realized that the exome-seq data doesn't cover the promoter region and I think RNA-seq data also doesn't cover promoter region. My advisor tell me to find another data set which cover the promoter region but I think to find the correct data set is not that easy because my gene target is known to be transcribed in the liver and I need to find normal - cancer cohort sample. So, first question is, do you have any suggestion for me how to find the mutation which occur in promoter region or it is just impossible? I have read another similar question and the answer seems confusing to me. And the second question, do you have any suggestion how to find / to filter publicly available data which is really fit for my need? I only familiar with NCBI Geodata sets but I don't know other online resource. Thank you very much for any suggestion you have.