Reelin is transcribed 4 genes away from acetylcholinesterase. And is a core collagen component. No wonder it's tied to Alzheimer's..
Here's a link that shows ACHE (acetylcholinesterase) and RELN (reelin) in the same view.
https://genome.ucsc.edu/cgi-bin/hgTracks?db=hg38&lastVirtMod...
The place that I saw this in my own work was in the way that ends of intervening sequence (introns) was coded for excision during expression of proteins. The different ends of different introns behaved differently and introns in different parts of genomes had slightly different dialects.
The relationship of similarity and locality in regulators is different from this, but is another case of proximity being a proxy for similarity.