Loss of dlx5a function increases the penetrance of mef2ca-associated phenotypes.
(A) Animals double heterozygous for mef2ca and dlx5a were intercrossed, raised to 6 dpf and fixed and stained with Alcian Blue (cartilage) and Alizarin Red (bone). Genotyped animals were flat mounted and imaged. In this family, dlx5a homozygous mutants appear wild type. But, removing functional copies of dlx5a increases mef2ca mutant penetrance. This includes phenotypes that we interpret to be ventral-to-dorsal transformations: br-to-op transformation (arrowheads), and ch-to-hm transformation (red arrow). Scale bar: 50 μm. (B) Genotyped mef2ca;dlx5a skeletal preparations were scored for penetrance of mef2ca-associated phenotypes. Asterisks indicate significance at alpha = 0.05 Fisher’s exact test compared with dlx5a+/+. (C, D) Genotyped mef2ca;dlx5a skeletal preparations were scored for penetrance of dlx5a-associated phenotypes.