[Hereditary hematopoietic malignancy with emphasis of juvenile chronic myelogenous leukemia and 7 monosomy syndrome].

Children with type 1 neurofibromatosis (NF-1) are at increased risk of myeloproliferative disorders (MPD). NF-1 gene was supposed to be a tumor suppressor gene. The majority of MPD patients in children with familial NF-1 inherited the disease from their mother. Loss of heterozygosity (LOH) of NF-1 gene has been reported in juvenile chronic myelogenous leukemia (JCML) and 7 monosomy syndrome (7MS) patients with NF-1. On the contrary, no LOH of NF-1 gene was found in these patients without NF-1. NF-1 gene is considered to be involved in the pathogenesis of JCML and 7MS with familiar NF-1. Other familiar hematopoietic malignancy, such as Fanconi's anemia, Down's syndrome and Li-Fraumeni syndrome are also discussed.