This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Medicine
Poorest prognosis in AML is seen in which cyiogcnetic abnormality- 
Select and explain. 
A. Monosomy 7, B. No cytogenetic abnormality, C. t(l5,i7), D. inv, 16
A: Monosomy 7
Answer: A: Monosomy 7 
Explanation: Monosomy 7 or paial deletion of the long arm of chromosome 7 (7q-) is a frequent cytogenetic finding in the bone marrow of patients with myelodysplasia (MDS) and acute myelogenous leukemia (AML) Ref Davidson 23rd edition pg 789