MUTATIONAL ANALYSIS AND EXPRESSION STUDIES OF THE NEUROFIBROMATOSIS TYPE-2 (NF2) GENE IN A PATIENT WITH A RING CHROMOSOME-22 AND NF2

The case of a seriously disabled and retarded female patient with neur ofibromatosis type 2 (NF2) is reported. She suffered from bilateral ve stibular schwannomas, multiple intracranial meningiomas and neurinomas . The constitutional karyotype of the patient was 46,XX, r(22)/45,XX,- 22. A constitutional G to A transition in the proximal 3' untranslated region of isoforms 1 and 2 was identified in the patient's NF2 gene a nd shown not to affect differential splicing or mRNA stability. The in stability of the ring chromosome 22 with the associated loss of tumor suppressor genes on chromosome 22, in particular the loss of the NF2 g ene, are assumed to have caused multiple tumorigenesis in this patient .