Be careful in how you use the word "genre." It's bad enough that the publishing industry misuses it as a reflex. (There are only four genres... and all of prose fiction is one of them.) This topic concerns not genres, but marketing categories and strategies. That should be all of the hint you need: They are labels ordinarily applied after a given work has been completed and submitted, all too often by people who have not read the work.
In short, relax. Write what works. Let the publisher worry about how to finely categorize a work, particularly since as an author you have no way to know what the publisher already has in the eighteen-month-long pipeline between contract and publication of a first novel (that's a historical median — there are a lot of longer and shorter experiences, but it seems to have held fairly constant since the demise of the Copyright Act's Manufacturing Clause allowed publishers greater ability to use overseas printers).
That is not to say that you shouldn't do appropriate research to determine where to submit your finished work. It is only to say that the lead time is soooo long that you shouldn't try to write what seems hot today based on today's BookScan figures, or bestseller lists, or other similar data.