Is it possible for the email editor to fetch the contact's email address from a custom field?

Is it possible for the email editor to fetch the contact's email address from a custom field?

Hi, 

Suppose I have a secondary email address field on my ticket form. When I send an email to the customer, is it possible to fetch the email from that field instead of the default email field. That way, my "To" recipients will be the one on the custom field. Thank you.

Jordanne