9318381 Eanes Chromosomal rearrangements are a significant feature of animal and plant genomes, and are a significant cause of cancers. However, to date little is known about the features of the breakpoints of such arrangements. Using Drosophila melangaster as a model organism, this project will examine DNA sequence features associated with the chromosomal breakpoints of three inversions found to be polymorphic in natural populations. This will also examine the one fixed inversion difference between D. melangaster and D. simulans. The proposed investigation will use an established microdissection-polymerase chain reaction approach to efficiently recover genomic clones spanning breakpoints. The subsequent analysis of these clones and population samples of inverted and standard arrangements will permit evaluation of a number of hypotheses of long standing interest. These include determining whether rearrangements are each unique mutational events, and cause mutations in genes. It will also allow us to determine if some inversions are old. Overall, our study will contribute novel information specific to the mutational origin, phenotypic consequences, and population genetics of inversion polymorphism. The fruit fly species. Drosophila melangaster, is growing rapidly as a model of molecular change particularly with respect to variation in single genes. This study will add a unique and significant contribution to our understanding chromosomal rearrangements in general. p d z _ _ !u ! F _ _ ( Times New Roman Symbol & Arial " h Z E c e c e 7 Crystal Blackshear Crystal Blackshear
