Worldwide, only 75 people are known to suffer from Cantú syndrome. We don't know how many sufferers there really are: "The problem with rare diseases is that they often go undiagnosed," Anna Weinzinger from the Department of Pharmacology and Toxicology at the University of Vienna points out. Yet the symptoms of Cantú syndrome are relatively clear: Due to changes in skeletal muscle and bone structure, affected individuals usually have a similar phenotype, have strong hair growth over the entire body and a significantly enlarged heart muscle.

"More than two-thirds of all patients tested were found to have a mutation in the transporter protein or in the potassium channel," explains Weinzinger: "Since the protein does not function adequately, the body tries to counteract this and build up more muscle mass." The changes in the heart muscle are probably the biggest problem from a medical point of view: around 70 percent of Cantú patients are born with a heart defect that can only be corrected by operation. [more]