"creategene" may have a while to go until science catches up. And it'll take a bit longer for the industry itself to catch up with genetic engineering. Nevertheless, given the advances in research that have already been made, I'll hazard a guess.
A reseller might be around $20-$40 for this domain. You may be able to reach the low xxx with an end-user. Of course, if the field becomes more widely accepted, the value would increase in the future. Overall, it's a nice domain to have.