Characterization of a single base-pair deletion in neurofibromatosis type 1.

The gene which is responsible for neurofibromatosis type 1 (NF1) is located on chromosome 17 (17q11.2). The NF1 gene is approximately 350 kilobases (kb) long and exhibits an extremely high mutation rate; therefore, most patients are expected to have unique mutations. To date, relatively few mutations have been well characterized. We report here a de novo single base pair (bp) deletion in one NF1 allele in a patient diagnosed with NF1 and leukemia. We further characterized this mutation at the RNA level by allele-specific oligonucleotide (ASO) hybridization which demonstrated that the mutant allele is transcribed.