Triplication of the Ifnr locus is necessary for increased incidence of heart malformations in a mouse model of Down syndrome.

Images of haematoxylin and esoin stained sections of embryos from the Dp16 mouse model of Down syndrome, Dp16 corrected for <em>Ifnr </em>dosage (Dp16^2xIfnrs, Norm), and wildtype controls (WT), at E15.5. Upon harvest, embryos were fixed at 4°C overnight in 2% paraformaldehyde diluted in 1x PBS stored in 70% ethanol before embedding in paraffin. Embedded embryos were sectioned transversely at 7 µm thickness using a LEICA RM 2155 Rotary Microtome. Serial sections were collected then haematoxylin and eosin Y (H&amp;E) staining performed, followed by imaging with a Keyence BZ-X710 All-in-One Fluorescence Microscope. The investigators who sectioned embryos and performed H&amp;E analysis were blind to embryo genotype.