As we found that we could use Ki67 and cleaved caspase-3 staining to show that doxorubicin treatment caused decreased cell proliferation and increased cell death compared to vehicle treatment (Figure 5; Videos S2–S5), these data suggest that the zebrafish TNLMD model offers a tool for the successful analysis of the effects of drugs on cell markers of LMD proliferation and apoptosis. This evidence concerns the gene MKI67 and Langer mesomelic dysplasia.