A portrait of copy-number polymorphism in Drosophila melanogaster.

摘要: Thomas Hunt Morgan and colleagues identified variation in gene copy number Drosophila the 1920s 1930s linked such to phenotypic differences [Bridges CB (1936) Science 83:210]. Yet extent of chromosomes, chromosomal regions, or copies, importance this within species, remain poorly understood. Here, we focus on copy-number melanogaster. We characterize polymorphism (CNP) across genomic contrast patterns infer evolutionary processes acting variation. Copy-number D. melanogaster is nonrandomly distributed, presumably because a mutational bias produced by tandem repeats other mechanisms. Comparisons coding noncoding CNPs, however, reveal strong effect purifying selection removal structural from functionally constrained regions. Most CNP suggest that negative biases are primary agents responsible for shaping