Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Germline mutations in the SAMD9 and SAMD9L genes, located in tandem on chromosome 7, are associated with a clinical spectrum of disorders including the MIRAGE syndrome, ataxia-pancytopenia syndrome and myelodysplasia and leukemia syndrome with monosomy 7 syndrome. Germline gain-of-function mutations increase SAMD9 or SAMD9L's normal antiproliferative effect. This causes pancytopenia and generally restricted growth and/or specific organ hypoplasia in non-hematopoietic tissues. In blood cells, additional somatic aberrations that reverse the germline mutation's effect, and give rise to the clonal expansion of cells with reduced or no antiproliferative effect of SAMD9 or SAMD9L include complete or partial chromosome 7 loss or loss-of-function mutations in SAMD9 or SAMD9L. Furthermore, the complete or partial loss of chromosome 7q may cause myelodysplastic syndrome in these patients. SAMD9 mutations appear to associate with a more severe disease phenotype, including intrauterine growth restriction, developmental delay and hypoplasia of adrenal glands, testes, ovaries or thymus, and most reported patients died in infancy or early childhood due to infections, anemia and/or hemorrhages. SAMD9L mutations have been reported in a few families with balance problems and nystagmus due to cerebellar atrophy, and may lead to similar hematological disease as seen in SAMD9 mutation carriers, from early childhood to adult years. We review the clinical features of these syndromes, discuss the underlying biology, and interpret the genetic findings in some of the affected family members. We provide expert-based recommendations regarding diagnosis, follow-up, and treatment of mutation carriers.
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PMID:SAMD9 and SAMD9L in inherited predisposition to ataxia, pancytopenia, and myeloid malignancies. 2953 29

MIRAGE syndrome is a multisystem disorder characterized by myelodysplasia, infections, restriction of growth, adrenal hypoplasia, genital phenotypes, and enteropathy. Mutations in the sterile alpha motif domain containing 9 (SAMD9) gene which encodes a protein involved in growth factor signal transduction are thought to cause MIRAGE syndrome. SAMD9 mutations lead to an antiproliferative effect resulting in a multisystem growth restriction disorder. Though rare, a few patients with SAMD9 mutations were reported to have hydrocephalus and/or cerebellar hypoplasia on imaging. The neuropathologic features of MIRAGE syndrome have not been previously described. Here, we describe the postmortem neuropathologic examinations of 2 patients with a clinical diagnosis of MIRAGE syndrome and confirmed SAMD9 mutations. Common features included microcephaly, hydrocephalus, white matter abnormalities, and perivascular calcifications. One of the 2 cases showed marked cerebellar hypoplasia with loss of Purkinje and granule neurons as well as multifocal polymicrogyria and severe white matter volume loss; similar findings were not observed in the second patient. These cases demonstrate the variation in neuropathologic findings in patients with MIRAGE syndrome. Interestingly, the findings are similar to those reported in ataxia-pancytopenia syndrome caused by mutations in SAMD9L, a paralogue of SAMD9.
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PMID:The Neuropathology of MIRAGE Syndrome. 3210 87