Loss of chromosome 7 (“Monosomy 7”) occurs very frequently among adult and pediatric patients with myelodysplastic syndromes myelodysplastic syndromes: (my-eh-lo-diss-PLASS-tik SIN-dromez) A group of disorders where the bone marrow does not work well, and the bone marrow cells fail to make enough healthy blood cells. Myelo refers to the bone marrow. Dysplastic means abnormal growth or development. People with MDS have low blood cell count for at… (MDS) or bone marrow failure bone marrow failure: A condition that occurs when the bone marrow stops making enough healthy blood cells. The most common of these rare diseases are aplastic anemia, myelodysplastic syndromes (MDS) and paroxysmal nocturnal hemoglobinuria (PNH). Bone marrow failure can be acquired (begin any time in life) or can be… syndromes that progress to myelodysplasia. Monosomy 7 Monosomy 7: Describes the loss of one of the two number 7 chromosomes. "Mono" means one and "somy" comes from the word chromosome. A laboratory test called fluorescence in situ hybridization (FISH) detects monosomy 7 and other genetic abnormalities. Monosomy 7 can occur in adult patients… carries with it a poor prognosis, even following a bone marrow bone marrow: The soft, spongy tissue inside most bones. Blood cells are formed in the bone marrow. transplant. Better understanding why monosomy 7 results in MDS would give rise to newer therapies, more effective and less toxic than bone marrow transplant bone marrow transplant: A bone marrow transplant (BMT) is also called a stem cell transplant (SCT) or hematopoietic stem cell transplant (HSCT).The procedure replaces unhealthy blood-forming stem cells with healthy ones and offers some patients the possibility of a cure. But for many patients, a BMT is not an option due… . One important lead is that monosomy 7 cells express a defective receptor for the blood growth hormone hormone: A part of the endocrine system that serves as the body's chemical messengers. Hormones move through the bloodstream to transfer information and instruction from one set of cells to another. G-CSF. G-CSF stimulates the production of normal whole blood cells. Even though monosomy 7 is common, it is difficult to culture monosomy 7 cells in order to study them. Dr. Futami developed two special cell lines that express the defective receptor. These cells display abnormal proliferation and defective maturation that characterizes MDS cells. He used these two cell lines to identify the biochemical changes that make the monosomy MDS cells different from normal blood cells, and found that defective receptor leads to unusual phosphorylation of Jak2. Dr. Futami and his colleagues expected that this abnormal Jak2 phosphorylation would be treated with novel agents. As expected, a Jak2 inhibitor BSK805 clearly inhibited abnormal growth of cells with defective receptor. He also found that defective receptor leads to abnormal gene expression of transcription factors which cause ineffective maturation of blood cells. These results will provide a clue to develop new types of therapies to correct this disease.