Fig. 1: scRNA-seq analysis of the fetal liver and bone marrow in Down syndrome.

a, Experimental workflow. Cells (CD45⁺, CD34⁺Lin⁻ and CD235a⁻) from fetuses with disomy and Ts21 were isolated from the bone marrow (femur) and the liver and processed for scRNA-seq. CD45⁺ cells from the fetal liver (number of fetus (k) = 3) were processed for multiome, and tissue sections from fetuses with disomy (k = 5) and Ts21 (k = 11) were used for spatial transcriptomics. Illustrations adapted from ref. ⁵⁰, Springer Nature Limited. b, 3D uniform manifold approximation and projection (UMAP) visualization of cells from Ts21 liver (number of cells (n) = 780,299, k = 15), Ts21 femur (n = 162,775, k = 12), disomic liver (n = 110,671, k = 3) and disomic femur (n = 53,807, k = 3) coloured by broad cell-type categories. NK, natural killer. c, Stacked barplot of relative abundances of different broad cell types in fetuses with Ts21 and disomy. The arrows indicate a significant increase or decrease in cell number in the Ts21 liver compared with the disomic liver. The difference in cell proportion was tested by a two-sided Wilcoxon rank-sum test with significance determined at FDR < 0.1.