Severe phenotypes have been described in patients with large deletions (∼5–10%) in the NF1 region, including learning disabilities, facial dysmorphic features, and cardiovascular malformations.9–11 For patients with intragenic NF1 mutations (representing more than 90% of cases),12–15 no clear allele-phenotype correlations have been established to date. This evidence concerns the gene NF1 and learning disability.