[Electric channels, genetics and cardiac sudden death. Brugada syndrome as an example].

Since the introduction of molecular biology techniques hereditary diseases can be studied. These techniques allow us to locate the gene that causes a disease in a family. The identification of this gene not only permits to diagnose and potentially treat those affected by the abnormal gene, but also helps in a better understanding of the pathophysiology and molecular basis of non-familial forms of the disease. Although these techniques have been incorporated slowly in the field of cardiology, now the speciality is completely submerged in molecular biology. The first gene that was found was that of hypertrophic cardiomyopathy, in 1989. Since then, we have advanced in all heart family illnesses. Hypertension, arteriosclerosis, congenital diseases and arrhythmias have benefited from these techniques. The understanding of arrhythmias that cause familial sudden death due to long QT syndrome or Brugada syndrome has progressed a lot. The first genetically guided therapy studies have shown that in the near future patients will receive a therapy according to their genetical default. Looking how fast these techniques are evolving, and the impressive advances of the Human Genome Project, probably the remaining genes causing familial diseases will be described in the coming years. These results are very encouraging and indicate a clear need to make a genetic diagnosis in all patients with these diseases. The diagnostic and therapeutic implications of these findings can be of enormous importance for our patients.