It is against the law to rent a house based on a person's gender. It might violate the Fair Housing Act if a landlord advertises to appeal to a certain gender preference. However, when looking for a roommate that shares common areas, it is not prohibited to target a certain gender.
The information in this answer is general in nature and is not legal or insurance advice for your specific situation. Policy language varies carrier by carrier; your declarations page is the final word. If you're unsure, call your agent before you need to file.