Table 2

Estimation of the de novo NF1 mutation rate in NF1 families

NF1 offspringDe novo NF1 mutation rate in NF1 families
Healthy*Familial NF1 variantNew NF1 variantTotal
Familial NF1 (n=246)260446†4710Observed: 2.81×10–3
Expected: 2×10–4; p=6.55×10–3
Expected: 3×10–5; p=1.9×10–5
NF1 families with >1 affected individuals tested (n=154)1643464514Observed: 3.89×10–3
Expected: 2×10–4; p=8.88×10–4
Expected: 3×10–5; p=3.31×10–7
  • *Paediatric cases, clinically determined by the absence of NF1 features.

  • †100 patients without genetic testing. Assumed to harbour the familial variant; n indicates the total number of families studied.

  • NF1, neurofibromatosis type 1.