Characterization of a de novo 48,XX,+r(X),+r(17) by in situ hybridization in a patient with neurofibromatosis (NF1).

We describe a patient with familial neurofibromatosis (NF1), short stature, developmental delay, and a de novo chromosome abnormality. In situ hybridization was done using chromosome specific centromere probes to characterize the karyotype as 46,XX/47, XX,+r(X) (p11q11)/47,XX,+r(17) (p11q11)/48, XX,+r(X) (p11q11),+r(17) (p11q11). The NF1 mutation, as well as each supernumerary ring chromosome, may have played a role in perturbing the normal developmental process of this patient.