Myelodysplastic syndrome in NHD13 transgenic mice. (Ai) MGG-stained peripheral blood smear from control nontransgenic mouse no. 1094; normal platelets are indicated with an arrow. (ii) MGG-stained peripheral blood from mouse no. 1145 showing a giant platelet (arrow), polychromasia, and poikilocytosis. (B) High-power view of normal (i-ii, mouse no. 1093; iii, mouse no. 1094) and transgenic (iv, mouse no. 1101; v, mouse no. 1103; vi, mouse no. 1145) neutrophils stained with MGG; note hypersegmented neutrophils in iv and vi, and a pseudo-Pelger-Huet anomaly in v. (Ci) A normal megakaryocyte in bone marrow from nontransgenic control mouse (no. 1093). (ii-iii) Dysplastic megakaryocytes (arrows) from NHD13 transgenic mouse (no. 1101) showing hypolobulated nuclei and increased nuclear-cytoplasmic ratio. Erythroblasts with clefted nuclei are also seen, indicated with arrowheads. (Di) Normal erythroid precursors from a control, nontransgenic mouse (no. 1094). (ii-iii) Dysplastic, multinucleated erythroblasts (indicated with arrows) from NHD13 mice (nos. 1101 and 1145). (E) Agarose gel electrophoresis of genomic DNA isolated from transgenic (mouse no. 1103, lane 1) or nontransgenic (mouse no. 1093, lane 2) mouse bone marrow. Size standard (far left lane) is HindIII-digested λ-phage DNA. (F-G) Low-power and (inset) high-power view of H&E-stained bone marrow from NHD13 transgenic (F, mouse no. 1103) and nontransgenic control (G, mouse no. 1094).