Twenty-three of the 67 children in the cohort were born within this 2.5-year period , representing a 13 % incidence of Nijmegen breakage syndrome .
O O O O O O O O O O O O O O O O O O O O O B-DiseaseOrPhenotypicFeature I-DiseaseOrPhenotypicFeature I-DiseaseOrPhenotypicFeature O