Gene Coexpression and Evolutionary Conservation Analysis of the Human Preimplantation Embryos

Figure 4

Distributions of gene ages. Genes were classified into four groups based on their first appearance in the phylogeny: (a) Opisthokonta-Bilateria, (b) Sarcopterygii-Amniota, (c) Chordata-Euteleostomi, and (d) Mammalia-Eutheria. For each stage, the vertical axis shows the observed frequencies minus expected frequencies of gene ages. The asterisks denote significant enrichment () in a specific gene group for each stage.

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