Two Seville-based scientists of the Molecular Genetics Laboratory of Virgen Macarena Hospital have discovered the gene responsible for the hereditary Cushing’s syndrome, a disease that is the result of an increase of the blood cortisol level, a hormone produced by the adrenal glands; patients suffer a serious of symptoms such as obesity, marks in their face, chest and shoulders, sometimes with an infection and an increased quantity of urine and excessive thirst (which may indicate the excess of glucose in the blood), among others. According to the work carried out by doctors of the University Hospital, the fault is in the gene of the protein kinase A of chromosome 17. The mutation increases the quantity of cortisol in the blood anomalously, which shows the first symptoms when boys and girls reach puberty. ‘Generally, they begin to put on weight without a justified cause, their blood pressure increases, they have menstruation disorders and violet stretch marks can appear in their breasts, hips and legs’, said Alfonso Gentil, assistant lecturer of the Endocrinology Department of Virgen Macarena Hospital. This research work describes the mutation found in 12 families in France, the USA and Spain, and connects for first time the Cushing’s syndrome with a specific genetic anomaly. That’s why this disease can be eventually diagnosed in molecular genetics laboratories on a prenatal basis or before it becomes clinically apparent, as it will be possible to identify what relatives of a patient are disease carriers. This research was carried out at the Molecular Genetics Laboratory of Virgen Macarena Hospital, in Seville, and led by Dr. Miguel Lucas, from a study made in the Endocrinology and Nutrition Department by Dr. Gentil. It consisted on genetically assessing nine members of a family, where two of them -an 18-year-old girl and her aunt, in the 40’s- were already diagnosed and surgically treated to eliminate the syndrome. The clinical trials consisted of extracting the DNA from the blood in order to check the segregation and link to gene of the protein kinase A and after that, determinate the sequence. When the results were ready, the researchers of Virgen Macarena Hospital contacted Constantine Stratakis, a prestigious pathologist of Bethesda University, in Maryland, USA, who after learning of the Seville family case, put the Seville doctors in contact with the Cochin Institute of Paris in order to publish the work in the May edition of the international journal ‘Journal Clinical Endocrinology and Metabolism’.