This is going to cause a lot of confusion. When I say "a lot" I mean "most people."

Seriously, when a simple word like "Manta" (as in that big huge fish, the Manta Ray) gets confused as "Mantra" by up to at least 30 percent of customers, I think you'll have serious issues with that domain name.

If you wanted something shorter and cooler in the first place, you could try "dnalogy" - but people are still going to mess that up too. If you look at the domain, it's (unfortunately) a Geocities page about geneology where the first three letters are supposed to be "DNA"

Seems like most domains these days are already taken, or more than likely squatted. Even many nonsensical ones.

EDIT: If you act now, you can grab "dnaly.com" which is currently available. I still think a lot of people will mess it up, but it's about as short a domain as you'll find.