A comparative genomic analysis of the Drosophila dot chromosome. William G Neutzling, Melissa Jones, Genomics Education Partnership. Biology, McDaniel College, Westminster, MD.

   The process of annotation provides biological meaning and organization to the genome of an organism. In this project, we analyzed DNA sequence from two Drosophila species to identify genes and gene coordinates for subsequent comparative genomic analysis of the Drosophila dot chromosome. The tiny dot chromosome is of interest because it displays both euchromatic and heterochromatic properties that can vary between species. As a control for the dot chromosome, chromosome three was annotated in this project to serve as a euchromatic chromosome reference. Specifically, we annotated D. erecta Fosmid 55 and D. mojavensis DMAC 21 and DMAC 31. Within D. erecta Fosmid 55, we found six putative genes that corresponded to the following D. melanogaster orthologs: msn, dos, CG16984, RpL8, CG26985, and Pxn. In contrast, D. mojavensis DMAC 21 contained only one putative gene that was shown to be orthologous to D. melanogaster CG10566, whereas D. mojavensis DMAC 21 was found to not have any putative genes. The long-term goal of this project is to determine how DNA sequence information, including gene identity, gene density, and repeat density, influences higher order chromatin structure of the Drosophila dot chromosome. This research was performed in conjunction with a number of colleges and universities as part of the Genomics Education Partnership (GEP). The GEP provides undergraduate students the opportunity to participate in original comparative genomics projects, allowing students to contribute to public scientific databases and expand the understanding of how chromatin domains are assembled.