Published online in Genome Research this week, investigators at the University of Connecticut and the University of Michigan report their elucidation of the regulatory divergence in two closely related Drosophila species using deep mRNA sequencing. Between D. melanogaster and D. sechellia, 78 percent of expressed genes have divergent expression, the researchers write. They also found that cis-regulatory differences contributed to more expression divergence and showed more additive inheritance.