INTRODUCTION: Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder characterized by café-au-lait spots, neurofibromas, skinfold freckles, Lisch nodules, bone deformities, learning disabilities, and predisposition to neoplasms. It is caused by various mutations of the NF1 gene. Recently a 3-bp in-frame deletion in exon 17, c.2970-2972 delAAT mutation, has been associated with a milder phenotype of NF1 manifesting with pigmentary skin changes only. MATERIALS AND METHODS: We therefore analyzed 35 NF1 patients without neurofibromas, learning problems, or bone lesions (19 familial, 16 sporadic, age 7-44 years) for exon 17 mutations by DNA sequencing. RESULTS: We did not find the c.2970-2972 delAAT mutation in this group but identified two base changes in exon 17 (c.2989A>G and c.2894T>A), whether these two novel mutations are related to a mild phenotype remains to be confirmed in further studies. Our results suggest the reported phenotypic associations may not be valid for all populations.
INTRODUCTION:Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder characterized by café-au-lait spots, neurofibromas, skinfold freckles, Lisch nodules, bone deformities, learning disabilities, and predisposition to neoplasms. It is caused by various mutations of the NF1 gene. Recently a 3-bp in-frame deletion in exon 17, c.2970-2972 delAAT mutation, has been associated with a milder phenotype of NF1 manifesting with pigmentary skin changes only. MATERIALS AND METHODS: We therefore analyzed 35 NF1patients without neurofibromas, learning problems, or bone lesions (19 familial, 16 sporadic, age 7-44 years) for exon 17 mutations by DNA sequencing. RESULTS: We did not find the c.2970-2972 delAAT mutation in this group but identified two base changes in exon 17 (c.2989A>G and c.2894T>A), whether these two novel mutations are related to a mild phenotype remains to be confirmed in further studies. Our results suggest the reported phenotypic associations may not be valid for all populations.
Authors: A B Trovó-Marqui; E M Goloni-Bertollo; N I Valério; E C Pavarino-Bertelli; M P Muniz; M F Teixeira; J R Antonio; E H Tajara Journal: Braz J Med Biol Res Date: 2005-08-26 Impact factor: 2.590