Editor—Neurofibromatosis type 2 (NF2) is an autosomal dominant disorder that predisposes to bilateral vestibular schwannomas and other nervous system tumours. Two clinical subtypes have been proposed. The severe type (Wishart) has an onset before 25 years of age, a rapid course, and multiple nervous system tumours. The mild type (Gardner) has a later onset with a more benign course, often restricted to bilateral vestibular schwannomas.1

The NF2 tumour suppressor gene is localised on chromosome 22q12 and encodes a protein called merlin or schwannomin, which is related to a family of cytoskeleton associated proteins.2 3 Since the identification ofNF2, various germline mutations have been identified,4-6 as well as somatic mutations.7 In general, germline mutations associated with a mild phenotype include missense mutations and small in frame deletions or insertions.5

In our study, the proband (III.2) is an 18 year old boy with a mild facial palsy. Slight enlargement of both vestibular branches of the eighth cranial nerve was observed after …