(A) Comparative qPCR of Armh1, Armh2, Armh3 and Armh4 mRNA relative expression levels in isolated E11 embryo and adult hearts. Neither Armh1 nor Armh2 were detectible in embryo or adults hearts, whilst some Armh3 expression was present it was at considerably lower levels than Armh4 (32.1 Armh3 vs. 27.9 Armh4 median cycles in E11). (B) Quantitative PCR of Armh4 mRNA levels during heart morphogenesis, in microdissected isolated pooled (n=3) hearts (E10, E12 and E14) and isolated newborn and adult (8 week old) hearts. Note Armh4 levels decrease as the heart matures. qPCR analysis was performed in technical triplicate and data are presented as a logarithmic plot of relative expression, where a value of 1 indicates no difference between adult heart in A and B (indicated via *); and values <1 indicate reduced and >1 indicate increased expression. Error bars represent sd (fold change).