We are interested in the mechanisms by which cells regulate their gene expression patterns stably and heritably. Stable inheritance of distinct transcriptional states that persist through numerous cell divisions is critical for the formation of cellular identities during development. Several cis- and trans-acting factors govern this process. In eukaryotes, posttranslational modification (PTM) of histone tails, targeted by sequence-specific events to different regions of the chromosome, lead to alterations in chromatin structure and gene expression patterns, which can be inherited in cis following DNA replication. This process operates to create specialized chromosomal structures, such as those found at centromeres, telomeres and other repetitive DNA elements, which are maintained in a compact structure, called heterochromatin. Stability and heritability of heterochromatin is critical for the maintenance of genomic stability in eukaryotes. We use the fission yeast as a model for understanding the molecular mechanism of heterochromatin formation and its role in preventing spurious recombination among repetitive DNA elements. Graduate students in our lab can expect to use a wide range of genetic, biochemical, genomic and proteomic tools to ask fundamental questions about the underlying molecular mechanisms governing epigenetic pathways. Our goal is to uncover conserved mechanisms by which aberrations to epigenetic pathways contribute to the development of human diseases, especially cancers.