Genotype-phenotype correlation in type 1 neurofibromatosis: pMet992del mutation and milder disease.

A few genotype-phenotype correlations have been described in type 1 neurofibromatosis. One deletion, p.Met992del, seems to be responsible for a mild form of the condition, in which there is absence of externally visible neurofibromas. We report a mother and a son with this mutation.