Children with 5′-end NF1 gene mutations are more likely to have glioma

OBJECTIVE To ascertain the relationship between the germline NF1 gene mutation and glioma development in patients with neurofibromatosis type 1 (NF1). METHODS The relationship between the type and location of the germline NF1 mutation and the presence of a glioma was analyzed in 37 participants with NF1 from one institution (Washington University School of Medicine [WUSM]) with a clinical diagnosis of NF1. Odds ratios (ORs) were calculated using both unadjusted and weighted analyses of this data set in combination with 4 previously published data sets. RESULTS While no statistical significance was observed between the location and type of the NF1 mutation and glioma in the WUSM cohort, power calculations revealed that a sample size of 307 participants would be required to determine the predictive value of the position or type of the NF1 gene mutation. Combining our data set with 4 previously published data sets (n = 310), children with glioma were found to be more likely to harbor 5'-end gene mutations (OR = 2; p = 0.006). Moreover, while not clinically predictive due to insufficient sensitivity and specificity, this association with glioma was stronger for participants with 5'-end truncating (OR = 2.32; p = 0.005) or 5'-end nonsense (OR = 3.93; p = 0.005) mutations relative to those without glioma. CONCLUSIONS Individuals with NF1 and glioma are more likely to harbor nonsense mutations in the 5' end of the NF1 gene, suggesting that the NF1 mutation may be one predictive factor for glioma in this at-risk population.