Certain genetic alterations suppose a greater risk of cancer in the patients and their direct relatives. To detect these alterations, the Hospital Quirónsalud Torrevieja has acquired an automatic capillary sequencer, which determines the sequence of the gene to be studied. Once it is verified that there is an altered gene, the genealogical tree is made and, after the clinical assessment by the Genetic Counseling Unit, the patient and his family members are informed of the existing risk and the possibilities of preventive action. The unit is also responsible for evaluating genomic profiles for the prediction of effectiveness of antineoplastic agents, this being a work recently incorporated into the traditional work of the units of Genetic Counsel, as it began doing in other countries such as the United States.