Over a hundred ELANE mutations have been found in SCN1. This same gene is mutated in cyclic neutropenia. SCN2 is caused by heterozygous (autosomal dominant) mutation of the GFI1 gene on chromosome 1p22. GFI1 is a repressor of several transcriptional processes, including ELANE, as well as miR-21 and miR-196b micro-RNAs which influence myelopoiesis. SCN3 is the "classical", autosomal recessive form of Kostmann disease which arises from homozygous mutations in the HAX1 gene on chromosome 1p22.1. About one third of SCN3 individuals also have neurological changes including seizures, learning disabilities, or developmental delay. SCN4 is caused by autosomal recessive mutation of the G6PC3 gene on 17q21. SCN4 is associated with structural cardiac abnormalities, enlarged liver, intermittent thrombocytopenia and a prominent superficial venous pattern. A subset of SCN4 has severe primary pulmonary hypertension and respiratory failure. SCN5 arises from autosomal recessive Thr224Asn mutation in the VPS45 gene on chromosome 1q21.2. Unlike classical Kostmann disease, SCN5 also has defective platelet aggregation (thrombasthenia) and myelofibrosis. This type is refractory to granulocyte colony-stimulating factor. There is an absence of lysosomes in fibroblasts and depletion of alpha granules in platelets. Accelerated apoptosis occurs in the neutrophils and bone marrow. X-linked SCN (SCNX) is caused by mutation in the WASP gene on Xp11.SCN occasionally may arise from SBDS mutations. Usage
Severe congenital neutropenia (SCN) is used as the overarching term for all diseases that affect myelopoiesis most prominently. Kostmann syndrome can restrictively refer to Kostmann disease specifically, or can be used synonymously with SCN as an umbrella term.
MRI scans can also confirm a diagnosis; abnormal low intensities can indicate iron accumulation in the brain. Prevention
Children of affected individuals are obligate carriers for aceruloplasminemia. If the CP mutations has been identified in a related individual, prenatal testing is recommended. Siblings of those affected by the disease are at a 25% of aceruloplasminemia. In asymptomatic siblings, serum concentrations of hemoglobin and hemoglobin A1c should be monitored.To prevent the progression of symptoms of the disease, annual glucose tolerance tests beginning in early teen years to evaluate the onset of diabetes mellitus. Those at risk should avoid taking iron supplements. Treatment
Treatment includes the use of iron chelating agents (such as desferrioxamine) to lower brain and liver iron stores, and to prevent progression of neurologic symptoms. This, combined with fresh-frozen human plasma (FFP) works effectively in decreasing liver iron content. Repetitive use of FFP can even improve neurologic symptoms. Antioxidants such as vitamin E can be used simultaneously to prevent tissue damage to the liver and pancreas. See also
Human iron metabolism
Iron overload disorder

References
External links

GeneReviews/NCBI/NIH/UW entry on Aceruloplasminemia
OMIM entries on Aceruloplasminemia