Hola, Emelly! Cuomo estas? [img]http://www.ichthyosis.com/ubb/wink.gif
My Portuguese is a bit rusty, so I'll stick to English for now.
I'm not affected, but my children are. I am currently taking a beginning ballet class and was a gymnast in high school. I also took karate way back when. Having those experiences, I'd say that what you can do really depends on what you can tolerate, not what your mom says.
My sons' biggest problems are their hands and feet - any kind of pressure causes big cracks in the heels and palms. Because of that, I don't ever see them playing contact sports like basketball or American football. Also, all the running and jumping would aggravate the skin, so track and gymnastics aren't realistic. However, I would happily enroll my children in ballet or jazz, so long as they could wear jazz shoes, not ballet slippers.
One thing that helps my boys is taking a shower immediately before and after activities that we know will stress the cracking.
Personally, I'd start with ballet - it is mostly about stretching gently, not so much hard landings and rolling and whatnot like gymnastics. In my town, we have classes offered through the city park district which are short terms and pretty cheap for residents - much cheaper than signing up at a full-time studio. If you have something like that, you might be able to try it out before committing to something beyond your capabilities. If not, call a few studios. Some offer a trial free or reduced-fee class or two, or would make an exception for you upon hearing your situation.