Myelofibrosis (MF) in the pediatric setting is uncommon and appears to be pathogenically heterogeneous. MF due to intrinsic bone marrow abnormality (IMF) is distinct from adult-type Primary myelofibrosis (PMF) as they can lack the common genetic markers of clonality. To date, all but two reported patients with pediatric MF and mutated MPIG6B have been Arabic, and all reported cases have had a family history of consanguinity. Here we report the first North American patient of European ancestry with pediatric MF in whom novel compound heterozygous mutations of MPIG6B were identified.