For example, histone methylation can direct DNA methylation patterns, and DNA methylation can serve as a template for some histone modifications after DNA replication.40 H3K27me3 itself is a repressive mark associated with gene repression,41 but Ezh2 can also control DNA methylation directly by regulating Dnmts.42,43 Here, we show that despite increased H3K27me3 at the MMP-9 promoter, its transcription is increased in diabetes. This evidence concerns the gene MMP9 and diabetes mellitus.