Renji gave a light sigh. "I cannot be certain, but perhaps a few individuals have predisposition it it. Our inbreeding may actually have irremediably doomed a few individuals and their subsequent progeny." he shook his head slowly. "I am not certain if we were all simply unlucky, but with my grandfather having this, as well as my father, and..." there was an awkward pause. "... I wish to improve the current treatments and drug that are used. I wish to find a cure... someday."