Fig. 1

Case1 A–C: The 36-week ultrasound findings of the foetus. A Foetal heart enlargement. B The liver of the foetus was enlarged. C The foetus had an enlarged spleen. D Results of MRI of the foetal abdomen: The foetus had a markedly enlarged liver and spleen. E Cord blood film showing blast cells (Case 1) (10 × 100 magnification): The characteristic megakaryoblasts are visible microscopically, the blasts have typical morphology showing fine chromatin with prominent nucleoli and high nuclear cytoplasmic ratio. F Electrophoretograms of multiplex QF-PCR amplification with STR markers on chromosomes 18,13 and 21. Electrophoretic profiles observed for trisomy 21 foetus (red boxes). G Image from the Affymetrix Chromosome Analysis Suite Software showing trisomy 21. The location of the chromosomal repeat segments is denoted by the red boxes. H Histological findings of the foetal liver (Case 1) (Hematoxylin & Eosin staining, 10 × 100 magnification): A large number of intrahepatic structures have been destroyed. Numerous granulocyte (arrow) and blasts are present. Consider this condition to be extramedullary hematopoiesis. I Identification of mutations in GATA1 by Sanger sequencing, as visualized by Chromas software. The base change is indicated by a red boxes. Mutation [NM_002049.4 c.220G > A (p. Val74Ile)] was detected in the foetus