[ML-3] The Best Teacher in Medicine is the Patients; The Discovery of Segawa Disease
Masaya Segawa, MD, PhD, the director of ‘Segawa Neurological Clinic for Children’ and one of the pioneers in the child neurology was the person with warm hearted, determined idea, and mission as a medical professional. His scientific interests and accomplishments covered wide range. One of the highlights was the discovery of Segawa disease. One day in 1970, a girl accompanied by her mother visited Dr. Segawa’s out patient clinic in the University of Tokyo. She was suffering from walking difficulty which worsened toward the evening. Mother told to Dr. Segawa that only good thing about this girl in spite of this motor symptom is she does not move much during sleep, and that mother does not need to go her bed room to see if her blanket is uncovered. This incidental remark of mother made Dr. Segawa to study polysomnography of the girl, which lead to understand decreased activity of dopamine system in the striatum is the essential pathophysiology of Hereditary Progressive Dystonia with marked diurnal fluctuation (HPD) later it was called as Segawa disease. L-Dopa was beginning to be used as the treatment of Parkinson disease. He had learned the differences of muscle tone of Parkinson disease and dystonia, and his idea of trying l-Dopa to HPD patients was the very remarkable moment. Extensive clinically oriented studies and collaborative researches lead Dr. Segawa to clarify the pathophysiological mechanism, biochemical abnormalities, and finally the discovery of the causative gene, GTP cyclohydrolase1 gene, collaborating with Dr. Ichinose who sequenced the GTP cyclohydroase1 gene.