Fig. 2

Genes with low variation between inbred twins tend to have evolutionarily conserved expression levels. a Scatter plots in light blue represent the relationship between variation in gene expression levels (x axis, differential expression levels between inbred twins) and intraspecies diversity (y axis, expression level difference calculated from Kasasa and Oura medaka embryos). Overlaid scatter plots in yellow represent the relationship between gene expression variation (x axis) and the technical error determined from technical replicates (y axis). b Relationships between gene expression variation as a reflection of stability in expression levels (x axis) and interspecies diversity (y axis) are shown for the macroevolutionarily conserved developmental period (st. 23.5) [7, 10, 12, 28] (left, medaka vs. zebrafish; centre, medaka vs. chicken; right, medaka vs. mouse). Spearman’s correlation coefficient between each variation of expression level is shown in each plot. P values are given for the test of no correlation. c Among the 10% of genes with the smallest variation detected at st. 23.5 and st. 28, representative genes associated with anatomical pattern development (GO:0048856) and anatomical structure formation involved in morphogenesis (GO:0048646) are shown. Tissues of expressed regions were referenced or deduced from studies in related vertebrates [36].