The prenatal period is a developmentally vulnerable time point during which environmental conditions, including nutrition, can have life-long impacts on health.1,2 This is particularly relevant to many childhood cancers that are thought to initiate during pregnancy.3 As a consequence, there has been intense interest in whether prenatal exposures can modulate childhood cancer risk.4-6 It is important to recognize that both maternal and offspring genetic factors including those in nutritional pathways may play an important role in pediatric cancer risk through their effect on the child's exposure to nutrients important in development during the prenatal period. The purpose of this research study is to evaluate whether there are any maternal or offspring genetic factors in the folate pathway that may contribute to the development of brain tumors in children with Neurofibromatosis Type 1 through analysis of DNA samples collected from families.