can you role your Rs?

I am just confused with this craziness of R rolling, is it really in your genes to have that ability? Is it a language acquisition? Is it a lingual ability, because if that is it, I am telling you there are few people in the United States that can do tricks with their tongue. I introduce myself to people simply by shaking hands and stating my name, Marrrrrta, I know by the look of most people that right away they have encountered a problem by having met me, they can't say my name. I really don't care if you role your Rs, Marta, is OK! (rhyme with Farta) but don't hide your lingual deficits by calling me Mirna, Marcia, Marla, or Marty, certainly if you can say the last two you can say Marta; fine just call me Babe! I love spell check, yes, I meant Farta!