von Hippel-Lindau syndrome: molecular diagnosis of two Lebanese families and analysis of the genotype-phenotype correlation

The von Hippel-Lindau syndrome (VHL) is a dominantly transmitted hereditary disorder associating multisystemic tumors affecting mainly the central nervous system, the kidneys, the pancreas, as well as pheochromocytomas. Mutations of the tumor suppressor gene VHL on chromosome 3 are responsible for the disease. This article reports for the first time the study of two Lebanese VHL affected families, presenting particularly hemangioblastomas of the central nervous system. Two different mutations of the VHL gene, S65W and F76S, respectively identified in the two families, confirmed the clinical diagnosis of the patients. Molecular diagnosis was then performed for at risk members of these families. This article reveals the importance of molecular diagnosis for suspected patients and of presymptomatic diagnosis for at risk members, especially that a close follow-up of carriers allows an early detection of tumors and prevents the metastasis stage, the most common cause of death of these patients.