Listing Promoters Of Segmental Duplications

Question

[Anima Mundi]

Hello,

as you know, genes of the same family due to segmental duplications may be present in cis on the same chromosome. In such cases, how could I extract the promoter FASTAs of those genes from a broad genomic range, avoiding to pick up all the other genes (belonging to different families)? I am interested mainly on the mouse genome.

Hope this is clear enough.